Printing-speed-responsive jaw spacing adjustment system for a jaw cylinder at the folding station of a web-fed printing press

BACKGROND OF THE INVENTION

1. Field of the Invention

This invention relates to a folding station appended to a web-fed printing press, as in newspaper production, for cutting the printed paper web into sections and folding the successive web sections each in the middle into the form of signatures. More particularly, the invention deals with a jaw cylinder at the folding station which has sets of fixed and movable jaws arranged at circumferential spacings thereon for folding the web sections as they are thrust into the jaw cavities. Still more particularly, the invention pertains to a system for automatically adjusting the spacing between the fixed and movable jaws to the operating speed of the printing press.

2. Description of the Prior Art

The web sections to be engaged by the jaws on the jaw cylinder are subject to substantive change in thickness even in the limited case of newspaper production. The paper in use may itself vary in thickness. What is more, the pages of each signature to be produced can vary considerably in number as two or more webs are concurrently printed and superposed one upon another before being fed into the folding station for production of multiple-page signatures. The spacing between each set of fixed and movable jaws must be adjustable to such widely different thicknesses of the web sections to be folded, in order to create proper folds without doing any harm to the printed paper. The jaws must nevertheless capture the web sections firmly enough to avert accidental disengagement as the web sections are subsequently folded into signatures.

Japanese Patent Publication No. 7-55761 is hereby cited as prior art on the subject of jaw spacing adjustment. It teaches to sense the thickness of the printed web or webs being introduced into the folding station and to vary the spacing between the fixed and movable jaws accordingly.

More recently, however, such thickness-dependent adjustment of jaw spacing has proved insufficient for the proper functioning of the jaw cylinder as a result of remarkable rise in the running speed of the printing press. Let it be supposed that the jaw spacing is now set properly for a given web thickness and at a given running speed of the press. Then, according to the prior art thickness-dependent adjustment of jaw spacing, the web sections were easy to fall off the jaws when the press speed was made higher, particularly in the case of production of multiple-page signatures.

Let us now briefly study the makeup of the folding station of the rotary printing press in order to learn in some more detail the problems involved in jaw spacing adjustment. The folding station has a cutter cylinder and a folding cylinder in addition to the jaw cylinder, which cylinders are all in constant rotation during the progress of printing. The printed web of paper is first wrapped around part of the folding cylinder and, while traveling thereover, cut into successive sections by cutting blades on the cutter cylinder which is held against the folding cylinder via the web. The folding cylinder is equipped with elongate folding blades each extending parallel to the folding cylinder axis and arranged at circumferential spacings thereon. Each folding blade is movable radially of the folding cylinder.

Pushed off the surface of the folding cylinder by one of the folding blades, each web section has its midpart inserted in one of the elongate jaw cavities which are cut in the surface of the jaw cylinder at circumferential spacings. The midpart of the web section that has been pushed into the jaw cavity is therein engaged, together with the folding blade, between the fixed and movable jaws as the movable jaw is closed against the fixed jaw, and thereby folded along the centerline of the web section. The web section is subsequently carried away from the surface of the folding cylinder by the jaw cylinder as these cylinders continue rotation in opposite directions. The folding blade withdraws from between the fixed and movable jaws just after the web section has been thereby engaged, so that the web section is folded along the centerline while being carried away from the folding cylinder.

When the web section is pulled off the folding cylinder as above after having its midpart captured by the jaws, the leading half of the web section must travel in sliding contact with the folding cylinder. An inertial force will then act on the web section, tending to pull the web section out of engagement with the jaws in opposition to spring pressure being exerted on the jaws. The greater the mass of the web section, or the more the number of webs superposed, the stronger will be the centrifugal pull of the web section. Actually, the web sections fell off the jaws in the worst case.

Obvious solutions to this problem might be to make the jaw spacing narrower, to employ heavier springs for the movable jaws, or both. These solutions are unsatisfactory because, at lower running speeds of the press, ink offset would occur between the contacting surfaces of the web sections being folded.

SUMMARY OF THE INVENTION

The present invention seeks, in connection with the folding station of a rotary printing press, to automatically adjust the jaw spacing to the running speed of the printing press in order to minimize the risks of accidental disengagement of the web sections from the jaws and of ink offset between their contacting surfaces.

Another object of the invention is to make automatic adjustment of the jaw spacing depending not only upon the running speed of the press but also upon the mass of each web section to be folded or the pages of the signatures to be made.

In summary the present invention concerns a speed-responsive jaw spacing adjustment system for a jaw cylinder at the folding station of a web-fed printing press where one or more webs of printed paper are cut into successive sections, and each web section folded into a signature. The jaw cylinder is conventionally furnished with a fixed and a movable jaw, the latter being movable toward and away from the former for engaging and folding each web section as its midpart is inserted therebetween. The fixed and movable jaws are, moreover, mounted to separate, independently movable parts of the jaw cylinder which are coupled to jaw spacing adjustment means to permit adjustment of the spacing therebetween in any operating phase of the movable jaw relative to the fixed jaw. The jaw spacing adjustment means have their own drive means including a bidirectional electric drive motor such as a stepper motor.

For controllably energizing the drive motor according to the running speed of the printing press, the jaw spacing control system comprises a press speed circuit for providing a press speed signal indicative of the speed at which the web is currently being fed into the folding station, and a jaw spacing circuit for providing a jaw spacing signal indicative of the current actual spacing between the fixed and the movable jaw. Connected to these circuits is a jaw spacing adjustment circuit which puts out, in response to the incoming press speed signal and jaw spacing signal, a jaw spacing adjustment signal for adjustment of the jaw spacing to the current press speed. The jaw spacing adjustment circuit has its output connected to the drive motor for causing the same to drive the jaw spacing adjustment means in response to the jaw spacing adjustment signal.

More specifically, the jaw spacing adjustment circuit responds to the incoming press speed signal by determining an optimal jaw spacing for the current press speed and compares this optimal jaw spacing with the actual jaw spacing indicated by the jaw spacing signal. If a difference proves to exist between the desired and the actual jaw spacing, then the adjustment circuit produces the jaw spacing adjustment signal for elimination, or reduction to a tolerable range, of that difference.

Preferably, in cases where the printing press is designed for concurrent printing of a variable number of webs for production of signatures of a variable number of pages, the jaw spacing may be adjusted not only to the press speed but also to the number of webs to be processed jointly. Toward this end there may be additionally provided an input device for inputting data indicative of how many webs are processed simultaneously, and a memory for storing a table indicative of desired jaw spacings for various combinations of a series of different press speeds and a series of different web numbers. Inputting the web number data in addition to the press speed signal and actual jaw spacing signal, the jaw spacing adjustment circuit can be made to read out from the memory the desired jaw spacing suiting the particular combination of the current press speed and current web number.

Thus, at whatever speed the press may be run, the jaw spacing is automatically readjusted to that press speed for engaging and folding the web sections under optimum pressure. The web sections of any of predetermined different thicknesses are not to accidentally fall off the jaws at high press speed, nor is ink offset to occur between their contacting surfaces at low press speed. All in all, the jaw spacing adjustment system has proved to contribute immensely to the production of printings of invariably high quality and to the reduction of press downtime.

The above and other objects, features and advantages of this invention will become more apparent, and the invention itself will best be understood, from a study of the following description and appended claims, with reference had to the attached drawings showing the preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1

is a diagrammatic illustration of a folding station of a web-fed printing press including a jaw cylinder to which is applicable the present invention;

FIG. 2

is a fragmentary, developed sectional view (taken along the planes of lines II—II in

FIGS. 5 and 7

) of the jaw cylinder of

FIG. 1

shown together with jaw spacing adjustment means and drive means therefor;

FIG. 3

is a section taken along the line III—III in

FIG. 2

;

FIG. 4

is a section taken along the line IV—IV in

FIG. 2

;

FIG. 5

is a section taken along the line V—V in

FIG. 2

;

FIG. 6

is an enlarged, fragmentary section taken along the line VI—VI in FIG.

2

and showing one movable jaw part together with the fixed jaw;

FIG. 7

is an end view of the jaw cylinder apparatus as seen in the direction of the arrow VII in

FIG. 2

; and

FIG. 8

is a block diagram of the speed-responsive jaw spacing adjustment system for the jaw cylinder apparatus of FIGS.

2

-

7

.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Folding Station

The present invention is currently considered best applicable to the folding station of a rotary printing press that is constructed to print two or more webs of paper at the same time for joint processing into multiple-page signatures, although of course only one web of paper may be printed. As depicted diagrammatically in

FIG. 1

, the exemplified folding station F has a pair of feed rollers FN for frictionally introducing a continuous web or webs W of printed paper into the folding station F. Although in practice any required number of webs may be printed concurrently and introduced in superposition into the folding station F, it is assumed for simplicity of description that only one printed web W is now being fed into the folding station. The usual practice in the art is to fold the printed web longitudinally as by a former, not shown, which is positioned upstream of the folding station F.

The folding station F has a cutter cylinder F

1

, a folding cylinder F

2

, a jaw cylinder F

3

, and a delivery fan F

4

, for cutting the printed web W into sections PC, folding each web section in the middle into a signature, and delivering the successive signatures. All the cylinders F

1

-F

3

and the fan are F

4

rotatably mounted between a pair of confronting framing walls FF, one shown. A delivery conveyor FC underlies the delivery fan F

4

.

The cutter cylinder F

1

has one or more, two shown, cutting blades F

11

in circumferentially spaced-apart positions thereon, with each blade extending parallel to the cutter cylinder axis. The folding cylinder F

2

has a plurality of, five in this embodiment, anvils or beds F

22

at constant circumferential spacings on its surface for mating engagement successively with the cutting blades F

11

on the cutter cylinder F

1

. Rows of retractable piercing pins F

21

are also mounted to the surface of the folding cylinder F

2

, in positions immediately upstream of the anvils F

22

with respect to the arrow-marked direction of rotation of the folding cylinder. Wrapped around part of the folding cylinder F

2

, the web W will be engaged by the successive rows of piercing pins F

21

and cut transversely into sections PC as the two cutting blades F

11

on the cutter cylinder F

1

alternately engage in the successive anvils F

22

on the folding cylinder F

2

. The web sections PC will then ride on the folding cylinder F

2

with their leading edges held engaged by the piercing pins F

21

.

The jaw cylinder F

3

, which is shown to be of the same diameter as the folding cylinder F

2

, has defined in its surface a plurality, five in this embodiment, jaw cavities J

10

at constant circumferential spacings. Carried by the folding cylinder F

2

to a position opposite one of the jaw cavities J

10

in the jaw cylinder F

3

, each web section PC will have its leading edge released from the piercing pins F

21

as the latter then retract into the folding cylinder F

2

. Concurrently, the web section PC will have its midpart pushed by one of folding blade F

23

on the folding cylinder F

2

off its surface into one of the jaw cavities J

10

in the jaw cylinder F

3

. The inserted midpart of the web section FS is therein to be engaged by one set of fixed and movable jaws to be set forth in detail subsequently. The jaws are not shown in this figure for lack of space but merely indicated by the capital J.

The folding blade F

23

will be subsequently withdrawn out of engagement with the jaws J, leaving the web section PC captured by the jaws in order to be folded. As the folding cylinder F

2

and jaw cylinder F

3

continue rotation in opposite directions, the web section PC will ride from folding cylinder onto jaw cylinder and, by so doing, be folded along the centerline.

Positioned between jaw cylinder F

3

and delivery conveyor FC, the delivery fan F

4

has a plurality of vanes FA mounted slantingly on its surface to define pockets. The folded web sections or signatures PC are to drop successively by gravity from the jaw cylinder F

3

into these pockets on the delivery fan F

4

and thence onto the delivery conveyor FC.

The construction of the folding station F as so far described is conventional, and therein lies no feature of the instant invention. The novel features of the invention will appear in the course of the following detailed description of the jaw cylinder, sets of jaws together with their drive means, a jaw spacing adjustment, a drive mechanism for the jaw spacing adjustment, and electronic controls for automatic, speed-responsive adjustment of the jaw spacing.

Jaw Cylinder

Broadly, the jaw cylinder F

3

is constituted of the following three parts which are each of one-piece construction:

1. An inner end part

11

including a pair of inner end plates

11

a

and

11

b

,

FIGS. 2 and 3

.

2. An outer end part

12

including a pair of outer end plates

12

a

and

12

b

,

FIGS. 2 and 4

.

3. A core part

13

which forms the core of the jaw cylinder F

3

and upon which both inner end part

11

and outer end part

12

are mounted for independent rotation within limits.

The inner end part

11

additionally includes a plurality of, three shown in

FIG. 3

, ties

11

c

joining the pair of inner end plates

11

a

and

11

b

and forming parts of the surface of the jaw cylinder F

3

. One of the opposite longitudinal edges of each tie

11

c

is shaped into a fixed jaw J

13

forming a part of the jaw means set forth with reference to FIG.

3

. Each of the inner end plates

11

a

and

11

b

has cut therein at least two slots

11

d

each extending radially from its outer edge and terminating short of its inner edge surrounding the core part

13

. The outer ends of all the slots

11

d

are tightly closed by caps

11

e

. The purposes for which the slots

11

d

are provided will become apparent from the subsequent description of the jaw spacing adjustment.

The outer end part

12

likewise additionally comprises a plurality of, three shown in

FIG. 4

, ties

12

c

joining the pair of outer end plates

12

a

and

12

b

of approximately disc-like shape. A reference back to

FIG. 3

will reveal that each outer end part tie

12

c

is positioned between one inner end part tie

11

c

and one cap

11

e

, thus forming parts of the surface of the jaw cylinder F

3

. Each neighboring pair of inner end part tie

11

c

and outer end part tie

12

c

are spaced from each other circumferentially of the jaw cylinder F

3

to define one of the three jaw cavities J

10

set forth in connection with FIG.

1

. Each of the outer end plates

12

a

and

12

b

is shown to have three radial slots

12

d

,

FIG. 4

, cut therein for purposes to be set forth in connection with the jaw spacing adjustment. The outer ends of the slots

12

d

are firmly closed by caps

12

e

.

The core part

13

has a larger diameter portion

13

z

with a pair of smaller diameter portions

13

c

and

13

f

coaxially extending from its opposite ends. The larger diameter portion

13

z

of the core part

13

has a plurality of lugs

13

d

extending radially from its opposite ends in alignment along the jaw cylinder axis. Each aligned pair of lugs

13

d

are interconnected by a tie, not shown, extending parallel to the jaw cylinder axis. The pair of smaller diameter portions

13

e

and

13

f

of the core part

13

has rotatably mounted thereon the pair of inner end plates

11

a

and

11

b

of the inner end part

11

and the pair of outer end plates

12

a

and

12

b

of the outer end part

12

. A retainer plate

13

g

is secured to the left hand smaller diameter portion

13

g

.

Coaxially coupled to the smaller diameter portions

13

e

and

13

f

are a pair of journals

13

a

and

13

b

which are rotatably supported by the pair of confronting framing walls FF

a

and FF

b

. The right-hand journal

13

a

is mounted to the right-hand framing wall FF

a

via a set of bearings B

a

and bearing sleeve S

a

. The left-hand journal

13

b

is mounted to the left-hand framing wall FF

b

via a set of bearings B

b

, a bearing sleeve S

c

, another set of bearings B

c

around the bearing sleeve S

c

, and another bearing sleeve S

b

around the bearings B

c

.

The left-hand journal

13

b

of the jaw cylinder F

3

has a jaw cylinder drive gear GG mounted fast on its end projecting outwardly of the framing wall FF

b

. Driven by another drive gear DG, the drive gear GG is to impart rotation to the jaw cylinder F

3

. The jaw cylinder drive gear GG, as well as the other drive gear DG, takes the form of a helical gear as it is intended to perform additional functions in connection with the drive mechanism

30

for the jaw spacing adjustment

20

.

Jaws and Jaw Drive Means

Both

FIGS. 2 and 3

show a series of movable jaw parts J

12

in each of the jaw cavities J

14

. The movable jaw parts J

12

are mounted, in a manner to be detailed subsequently, to a jaw carrier shaft J

14

for joint pivotal motion into and out of web-section-folding engagement with the fixed jaw J

13

. The jaw carrier shaft J

14

itself is rotatably supported by the pair of outer end plates

12

a

and

12

b

of the outer end part

12

, as better illustrated in FIG.

4

. For convenience of description each series of movable jaw parts will be hereinafter referred to collectively as movable jaw, individually as movable jaw parts, and the same reference characters J

12

will be used in both cases.

FIG. 6

best illustrates how each movable jaw part J

12

is mounted to the jaw carrier shaft J

14

. Each movable jaw part J

12

is fastened or otherwise affixed to a movable jaw base J

19

which in turn is rotatably mounted to the jaw carrier shaft J

14

via a pair of axially-spaced-apart sleeve bearings which are not seen in this sectional view. A spring seat J

20

is fastened or otherwise secured to the jaw carrier shaft J

14

for joint rotation therewith, and a helical compression spring J

21

is mounted between movable jaw base J

19

and spring seat J

20

on one side of the jaw carrier shaft. On the other side of the jaw carrier shaft J

14

, the movable jaw base J

19

is biased by the compression spring J

21

into abutment against the spring seat J

20

via a member J

22

of wear-resistant material. This figure additionally reveals a torsion-bar spring J

18

which is built into the jaw carrier shaft J

14

to bias the same to turn clockwise as viewed in FIG.

6

.

The rotation of the jaw carrier shaft J

14

in a counterclockwise direction, as viewed in

FIG. 6

, in opposition to the force of the torsion-bar spring J

18

is therefore imparted to the movable jaw base J

19

via the spring seat J

20

and compression spring J

21

, causing the associated movable jaw part J

12

to move toward the fixed jaw J

13

. Upon clockwise rotation of the jaw carrier shaft J

14

, on the other hand, the spring seat J

20

will act directly and rigidly upon the movable jaw base J

19

to cause retraction of the movable jaw part J

12

away from the fixed jaw J

13

.

With reference back to

FIG. 2

the jaw carrier shaft J

14

rotatably extends through the right hand outer end plate

12

a

and has a crank arm J

15

mounted fast to its projecting end. The crank arm J

15

has a crankpin on which a cam follower roller J

16

is rotatably mounted for rolling engagement in a groove in a jaw drive cam J

17

of annular shape. The jaw drive cam J

17

is immovably mounted to the framing wall FF

a

via a bearing sleeve S

a

.

Thus, with the rotation of the jaw cylinder F

3

, the cam follower roller J

16

is to roll along the groove delineated by the jaw drive cam J

17

, thereby causing the crank arm J

15

to turn bidirectionally. The bidirectional turn of the crank arm J

15

is imparted directly to the jaw carrier shaft J

14

and thence, as has been set forth in conjunction with

FIG. 6

, to the movable jaw parts J

12

via the movable jaw bases J

19

, spring seats J

20

and compression springs J

21

. When the movable jaw J

12

is fully turned toward the fixed jaw J

13

, the compression springs J

21

will be compressed to variable degrees depending upon the thickness of the folded midpart of the web section PC caught therebetween. The variable degrees of compression of the compression springs J

21

determine variable amounts of energy thereby stored for acting on the respective movable jaw parts J

12

in order to cause the same to press the web section PC against the fixed jaw J

13

,

Jaw Spacing Adjustment

As has been mentioned, the fixed jaws J

13

are formed on the ties

11

c

of the inner end part

11

as in

FIG. 3

, whereas the movable jaws J

12

are rotatably supported by the pair of outer end plates

12

a

and

12

b

of the outer end part

12

as in FIG.

4

. It has also been stated that the inner end part

11

and outer end part

12

of the jaw cylinder F

3

are independently rotatable relative to the core part

13

. The spacings between the movable jaws J

12

and fixed jaws J

13

are therefore adjustable by varying at least either of the angular positions of the inner end part

11

and outer end part

12

on the core part

13

. The inner end part

11

and outer end part

12

are both concurrently angularly displaced in opposite directions by the jaw spacing adjustment

20

in this embodiment of the invention.

Employed for such concurrent angular displacement of the inner end part

11

and outer end part

12

, and hence of the movable jaws J

12

and fixed jaws J

13

, are two camshafts

14

and

15

,

FIG. 2

, which extend parallel to the jaw cylinder axis and which are equidistantly spaced therefrom. The camshaft

14

is designed to cause angular displacement of the inner end part

11

, and hence of the fixed jaws J

13

, relative to the core part

13

and so will be hereinafter referred to as the fixed jaw camshaft. The other camshaft

15

will then be hereinafter referred to as the movable jaw camshaft, being designed to cause angular displacement of the outer end part

12

, and hence of the movable jaws J

12

, relative to the core part

13

. The fixed jaw camshaft

14

and movable jaw camshaft

15

are both rotatably supported by the lugs

13

d

of the core part

13

via bearings B

d

and B

e

, and by the retainer plate

13

g

via bearings B

f

and B

g

, respectively.

As will be better understood by referring to

FIG. 3

in addition to

FIG. 2

, the fixed jaw camshaft

14

extends through the slots

11

d

in the pair of inner end plates

11

a

, and

11

b

and, with clearance, through the slot

12

d

in one outer end plate

12

b

. The fixed jaw camshaft

14

has two fixed jaw cams

16

mounted eccentrically thereon. The fixed jaw cams

16

are rotatably received in annular shoes

18

which in turn are received in the slots

11

in the inner end plates

11

a

and

11

b

and which are constrained to travel linearly of the slots

11

d

and in directions orthogonal to radii of the linearly of the slots

11

d

and in directions orthogonal to radii of the inner end plates

11

a

and

11

b

. Thus, when driven bidirectionally, the fixed jaw camshaft

14

will act upon the inner end part

11

via the fixed jaw cams

16

and shoes

18

, causing angular displacement of the fixed jaws J

13

with respect to the core part

13

.

A reference to both

FIGS. 2 and 4

will make it clear that the movable jaw camshaft

15

acts similarly on the outer end part

12

to cause angular displacement of the movable jaws J

12

. The movable jaw camshaft

15

extends through the slots

12

d

in the pair of outer end plates

12

a

and

12

b

and, with clearance, through the slots

11

d

in the pair of inner end plates

11

a

and

11

b

. The movable jaw camshaft

15

has two movable jaw cams

17

mounted eccentrically thereon. These cams

17

are rotatably received in annular shoes

19

which in turn are slidably received in the radial slots

12

d

in the outer end plates

12

a

and

12

b

for linear motion along the same. The bidirectional rotation of the movable jaw camshaft

15

is therefore translated, via the movable jaw cams

17

and shoes

19

, into the bidirectional angular displacement of the outer end part

12

around the core part

13

, causing the movable jaws J

12

to travel toward or away from the associated fixed jaws J

13

.

Projecting outwardly of the retainer plate

13

g

as in

FIG. 2

, both fixed jaw camshaft

14

and movable jaw camshaft

15

have pinions

21

and

22

mounted fast thereon. As pictured also in

FIG. 5

, these pinions

21

and

22

are the same in tooth number, pitch diameter, etc., and both mesh with a jaw spacing adjustment gear

23

which is coaxially fastened to the aforesaid bearing sleeve S

c

on the framing wall FF

b

. Also coaxially fastened to this bearing sleeve S

c

, on the outside of the framing wall FF

b

, is another jaw spacing adjustment gear

24

which is a helical gear of the same pitch diameter as the noted helical jaw cylinder drive gear GG on the jaw cylinder journal

13

b

. The teeth on this jaw spacing adjustment gear

24

, however, are twisted in a direction opposite to that of the teeth on the jaw cylinder drive gear GG. The jaw spacing adjustment gear

24

is driven by the drive mechanism

30

to be detailed presently.

Thus, upon rotation of the gear

23

in either direction, the pinions

21

and

22

will rotate in the same direction and at the same speed together with the fixed jaw camshaft

14

and movable jaw camshaft

15

. These camshafts

14

and

15

will impart their rotation respectively to the inner end part

11

of the jaw cylinder F

3

via the fixed jaw cams

16

and shoes

18

and to the outer end part

12

of the jaw cylinder via the movable jaw cams

17

and shoes

19

. The result will be the rotation of the inner end part

11

and outer end part

12

relative to the core part

13

through the same angle but in opposite directions, causing a change in the spacing between movable jaws J

12

and fixed jaws J

13

in any given position of the movable jaws relative to the fixed jaws.

Drive Mechanism for Jaw Spacing Adjustment

FIG. 2

best illustrates the drive mechanism

30

for jaw spacing adjustment, although it appears also in FIG.

7

. Included is a bidirectional electric motor

31

which preferably is a stepper motor of itself known construction and which will be hereinafter referred to as jaw spacing adjustment motor or simply as adjustment motor. Bracketed at

33

to a larger bracket

28

on the framing wall FF

b

, the jaw spacing adjustment motor

31

carries on its armature shaft a drive pinion

32

in mesh with a driven gear

28

f

. This driven gear is mounted fast to a lead screw

28

c

rotatably extending through a nut

28

e

nonrotatably supported by the bracket

28

. Therefore, upon bidirectional rotation of the adjustment motor

31

, the lead screw

28

c

will not only rotate but travel axially toward or away from the framing wall FF

b

in a direction parallel to the axis of the jaw cylinder F

3

. It is understood that the drive pinion

32

is of sufficient axial dimension to remain in mesh with the driven gear

28

f

throughout the stroke of the lead screw

28

c

.

The lead screw

28

c

is coupled endwise to a movable sleeve

28

b

which is mounted to a straight-splined shaft

28

a

cantilevered on the framing wall FF

b

. The lead screw

28

c

is rotatable, but restrained from axial displacement, relative to the movable sleeve

28

b

. It is therefore only the linear motion of the lead screw that is transmitted to the movable sleeve

28

b

, causing the same to travel linearly back and forth on the straight-splined cantilever shaft

28

a

. Rotatably mounted on the movable sleeve

28

b

are two helical pinions

25

and

26

of substantially one-piece construction jointly movable axially with the movable sleeve. The helical pinions

25

and

26

are in mesh respectively with the helical jaw cylinder drive gear GG and with the helical jaw spacing adjustment gear

24

.

Electronic Controls

As illustrated block-diagrammatically in

FIG. 8

, the electronic control system according to the invention is designed to control the jaw spacing adjustment

20

via the adjustment drive mechanism

30

. The control system includes a press speed circuit

50

which is shown comprising a press speed pulse generator

51

and a pulse counter

52

. In practice the press speed pulse generator

51

may take the form of a rotary encoder mounted to some revolving part of the printing press for provides a series of press speed pulses at a rate proportional to the running speed of the printing press. The pulse counter

52

may then count the incoming press speed pulses during each preassigned period of time and put out a press speed signal indicative of the press speed at that moment. The press speed signal is delivered to a jaw spacing adjustment circuit

90

.

Also delivered to the jaw spacing adjustment circuit

90

is a jaw spacing signal indicative of the actual current jaw spacing, from a jaw spacing circuit

70

. This circuit

70

is shown as a combination of a jaw spacing pulse generator

71

and an arithmetic unit

72

. Here again the jaw spacing pulse generator

71

may take the form of an incremental, bidirectional rotary encoder associated with the bidirectional stepper motor

31

of the jaw spacing adjustment drive mechanism

30

for providing a series of jaw spacing pulses indicative of how the stepper motor

31

is driving the jaw spacing adjustment

20

to vary the spacings between movable jaws J

12

and fixed jaws J

13

. Bidirectionally counting the jaw spacing pulses, the arithmetic unit

72

determines the actual current jaw spacing at any given phase of the pivotal motion of the movable jaws J

12

and puts out the jaw spacing signal indicative of that jaw spacing for delivery to the jaw spacing adjustment circuit

90

.

Incidentally, the arithmetic unit

72

should be held powered even when the printing press is out of operation. When the press is subsequently set into operation, the arithmetic unit

72

will then provide the jaw spacing signal indicative of the jaw spacing when the machine operation was discontinued.

Inputting both the press speed signal from the press speed circuit

50

and the jaw spacing signal from the jaw spacing circuit

70

, the jaw spacing adjustment circuit

90

causes the stepper motor

30

,

FIG. 2

, to be controllably energized for an optimal jaw spacing at the current running speed of the press. The jaw spacing adjustment circuit

90

includes a jaw spacing adjustment signal generator

91

to which are connected not only the press speed circuit

50

and jaw spacing circuit

70

but also an input device

100

for introducing data concerning the thicknesses of the web or webs to be handled at the folding station F, FIG.

1

.

More specifically, the input device

100

may be utilized for inputting both the thickness of the paper in use and the number of printed webs that are to be superposed for joint cutting and folding into signatures at the folding station. If the jaw spacing adjustment signal generator

91

is preprogrammed to choose from among a variety of known paper thicknesses, the paper thickness data may be input in terms of the tradename of the paper or of any arbitrary commodity number or name assigned thereto. Similarly, if the jaw spacing adjustment signal generator

91

is preprogrammed to choose from among several possible numbers of webs to be superposed, the web number data may be input in terms of the pages of the signatures to be produced.

Also connected to the jaw spacing adjustment signal generator

91

is a memory

92

on which there is stored Jaw Spacing Table such as that shown below. The Table indicates predetermined optimum jaw spacings for different combinations of different predetermined press speeds and different predetermined numbers of webs to be printed concurrently and processed jointly at the folding station, on the assumption that the paper in use is of standard thickness. The press speeds are given in terms of the number (the unit being 10,000) of signatures produced per hour, and the web number in terms of pages per signature. How the jaw spacing adjustment signal generator

91

utilizes this Table will become apparent in the course of the following description of operation.

JAW SPACING TABLE

PRESS

PAGES PER SIGNATURE

SPEED *

4

8

12

16

20

24

. . .

40

44

48

1

0.9

1.2

1.5

1.7

1.9

2.1

. . .

3.1

3.3

3.6

2

0.9

1.2

1.5

1.7

1.9

2.1

. . .

3.1

3.3

3.6

3

0.9

1.2

1.5

1.7

1.9

2.1

. . .

3.0

3.3

3.6

4

0.9

1.2

1.4

1.7

1.9

2.1

. . .

3.0

3.3

3.6

5

0.9

1.2

1.4

1.6

1.9

2.1

. . .

3.0

3.3

3.6

6

0.9

1.1

1.4

1.6

1.8

2.1

. . .

3.0

3.2

3.6

7

0.9

1.1

1.4

1.6

1.8

2.0

. . .

3.0

3.2

3.5

8

0.9

1.1

1.4

1.6

1.8

2.0

. . .

3.0

3.2

3.5

9

0.8

1.1

1.4

1.6

1.8

2.0

. . .

2.9

3.2

3.5

10

0.8

1.1

1.4

1.6

1.8

2.0

. . .

2.9

3.2

3.5

11

0.8

1.1

1.3

1.6

1.8

2.0

. . .

2.9

3.1

3.5

12

0.8

1.1

1.3

1.6

1.8

2.0

. . .

2.9

3.1

3.4

13

0.8

1.1

1.3

1.5

1.8

2.0

. . .

2.9

3.1

3.4

14

0.8

1.1

1.3

1.5

1.7

1.9

. . .

2.9

3.1

3.4

15

0.8

1.0

1.3

1.5

1.7

1.9

. . .

2.8

3.1

3.4

16

0.8

1.0

1.3

1.5

1.7

1.9

. . .

2.8

3.0

3.4

17

0.8

1.0

1.3

1.5

1.7

1.9

. . .

2.8

3.0

3.3

18

0.8

1.0

1.2

1.5

1.7

1.9

. . .

2.8

3.0

3.3

19

0.8

1.0

1.2

1.4

1.7

1.9

. . .

2.8

3.0

3.3

20

0.7

1.0

1.2

1.4

1.6

1.8

. . .

2.7

2.9

3.2

* × 10,000 signatures per hour.

The jaw spacing adjustment signal generator

91

has its output connected to a motor driver circuit

93

and thence to the stepper motor

31

,

FIG. 2

, of the jaw spacing adjustment drive mechanism

30

. The motor driver circuit

93

will controllably energize the stepper motor

31

for rotation in either of two opposite directions, causing the jaw spacing adjustment

20

to adjust the jaw spacing to the particular combination of the current running speed of the press and the number of webs to be processed in superposition. The jaw spacing is additionally adaptable for the thickness of the paper in use even if it deviates from the standard, as will become apparent from the following description of operation.

Operation

Preparatory to the commencement of each printing assignment, the operator or supervisor may introduce both paper thickness data and web number, or signature page, data into the jaw spacing adjustment signal generator

91

from the input device

100

. The web of paper W is to be threaded through the folding station F as indicated in FIG.

1

. As the printing press is set into operation, the cutter cylinder F

1

, folding cylinder F

2

, jaw cylinder F

3

and delivery fan F

4

will all rotate at the same peripheral speed. Traveling over the folding cylinder F

2

, the printed web W will be cut into successive sections PC by the cutting blades F

11

on the cutter cylinder F

1

in cooperation with the anvils F

22

on the folding cylinder.

In a position angularly spaced approximately three fifths of a complete revolution of the folding cylinder F

2

from where the web W is cut as above, each web section PC will have its midpart placed opposite one of the jaw cavities J

10

in the jaw cylinder F

3

. One of the folding blades F

23

on the folding cylinder F

2

will then push this midpart of the web section PC into the jaw cavity J

10

. Thereupon the movable jaw J

12

mounted in this jaw cavity will turn toward the fixed jaw J

13

, pressing the inserted midpart of the web section PC against the fixed jaw together with the folding blade F

23

. The movable jaw J

12

will be so actuated as the crank arm J

15

on the jaw carrier shaft J

14

is caused to turn counterclockwise, as viewed in

FIG. 6

, by the jaw drive cam J

17

with which the cam follower roller J

16

travels in constant engagement with the rotation of the jaw cylinder F

3

. The jaw carrier shaft J

14

will turn with the crank arm J

15

against the force of the torsion-bar spring J

18

built into it.

As will be understood by referring to

FIG. 6

again, the counterclockwise rotation of the jaw carrier shaft J

14

will be transmitted to the movable jaw parts J

2

via the spring seats J

20

, compression springs J

21

and jaw bases J

19

. The movable jaw parts J

12

will thus resiliently press the midpart of the web section PC against the fixed jaw J

13

as the compression springs J

21

undergo compression to variable degrees depending upon the total thickness of the doubled midpart of the web section PC and the folding blade F

23

, the latter being still caught in the former.

With the continued rotation of the folding cylinder F

2

and jaw cylinder F

3

, the folding blade F

23

will withdraw out of the jaw cavity J

10

in the jaw cylinder and retract into the folding cylinder, leaving behind the doubled midpart of the web section PC. Then the movable jaw J

12

will be urged by the compression springs J

21

to press the midpart of the web section PC against the fixed jaw J

13

and hence to fold the same along its centerline. Then, again with the continued rotation of the folding cylinder F

2

and jaw cylinder F

3

, the web section PC will come off the folding cylinder and be completely folded over the jaw cylinder.

As the folded web section PC rides over the jaw cylinder F

3

, the jaw carrier shaft J

14

will turn clockwise, as viewed in

FIG. 6

, under the influence of the jaw drive cam J

17

. The torsion-bar spring J

18

will assist such clockwise turn of the jaw carrier shaft J

14

. Turning clockwise with the jaw carrier shaft J

14

, the movable jaw J

12

will release the folded web section PC and so allow the same to fall by gravity off the surface of the jaw cylinder F

3

into one of the pockets defined by the slanting vanes FA,

FIG. 1

, on the delivery fan F

4

. The vanes FA are so angled with respect to this rotational direction of the delivery fan F

4

that the folded web section PC will subsequently slide down one of the vanes onto the underlying delivery conveyor FC thereby to be transported to a place of shipment.

The jaw spacing adjustment system according to the invention will be automatically triggered into operation upon commencement of printing. The press speed circuit

50

,

FIG. 8

, will ascertain the running speed of the press whereas the jaw spacing circuit

70

will compute the current spacing between the fixed and movable jaws. More specifically, at the press speed circuit

50

, the pulse counter

52

will count the output pulses of the press speed pulse generator

51

during each of successive preassigned periods of time and put out the press speed signal indicative of the press speed in real time.

At the jaw spacing circuit

70

, on the other hand, the arithmetic unit

72

will keep counting the jaw spacing pulses from their generator

71

and compute therefrom the actual jaw spacing at some particular operating phase of the jaw spacing adjustment drive means

30

, such phase being ascertainable from the incoming jaw spacing pulses. The arithmetic unit will send the resulting jaw spacing signal to the jaw spacing adjustment signal generator

91

, to which there will also be fed the press speed signal from the press speed circuit

50

.

Each time the input press speed signal renews itself, the jaw spacing adjustment signal generator

91

will respond by reading out from the Jaw Spacing Table on the memory

92

the particular jaw spacing to be established at the particular running speed of the press and with the particular number of webs being processed jointly.

Possibly, the thickness of the paper in use, input through the input device

100

, may deviate from the standard thickness on the basis of which the stored Table was formulated. In such cases the jaw spacing adjustment signal generator

91

will compute the jaw spacing to be provided for that thickness of paper, at the current running speed of the press and with the current number of webs, by the equation:

L=L

o

×(

t/t

o

)

where

L=the currently desired jaw spacing,

L

o

=the jaw spacing read out from the memory.

t=the thickness of the paper currently in use, and

t

0

=the standard paper thickness.

Then the jaw spacing adjustment signal generator

91

will proceed to compare the thus-computed desired jaw spacing with the actual jaw spacing being indicated at that moment by the jaw spacing signal from the jaw spacing circuit

70

. If the difference between the desired and the actual jaw spacing proves to exceed a preset limit, the jaw spacing adjustment signal generator

91

will cause the motor driver circuit

93

to energize the jaw spacing adjustment motor

31

. This motor will then rotate in such a direction, and through such an angle, as to optimize the jaw spacing at the current press speed and with the current number of webs being superposed.

The required angle of rotation of the jaw spacing adjustment motor

31

in the required direction will be translated by the lead screw

28

c

into the linear travel of the sleeve

28

b

on the straight-splined cantilever shaft

28

a

. The helical pinions

25

and

26

will travel axially with the sleeve

28

b

. Being in mesh with the helical jaw cylinder drive gear GG, which is locked against axial displacement, the helical pinion

25

on axial displacement will undergo angular displacement, too, together with the second helical pinion

26

.

The second helical pinion

26

is itself in mesh with the helical jaw spacing adjustment gear

24

, so that this gear will likewise turn upon linear travel of the second pinion

26

. Furthermore, since the second pinion

26

itself has been angularly displaced with the first pinion

25

by the jaw cylinder drive gear GG, this angular displacement of the second pinion will also be imparted to the jaw spacing adjustment gear

24

. The resulting rotation of this gear

24

will be transmitted via the sleeve S

c

to the other jaw cylinder drive gear

23

and thence to the pinions

21

and

22

on the fixed jaw camshaft

14

and movable jaw camshaft

15

.

With reference to both

FIGS. 2 and 3

the rotation of the fixed jaw camshaft

14

, on the one hand, will result in eccentric revolutions of the two fixed jaw cams

16

nonrotatably mounted thereon. Revolving within the annular shoes

18

, the fixed jaw cams

16

will cause the shoes to travel linearly along the slots

11

d

in the pair of inner end plates

11

a

and

11

b

of the jaw cylinder inner end part

11

and in directions orthogonal to the radii of the inner end plates. The shoes

18

in so doing will act on the inner end plates

11

a

and

11

b

, causing the entire jaw cylinder inner end part

11

to turn in one direction on the jaw cylinder core part

13

.

The rotation of the movable jaw camshaft

15

, on the other hand, will likewise result in eccentric revolutions of the two movable jaw cams

17

,

FIGS. 2 and 4

, which are nonrotatably mounted thereon. These cams

17

will revolve within the annular shoes

19

and so cause the same to travel linearly along the slots

12

d

, in the pair of outer end plates

12

a

and

12

b

of the jaw cylinder outer end part

12

and in directions orthogonal to the radii of the outer end plates. The complete jaw cylinder outer end part

12

will then rotate in the other direction on the jaw cylinder core part

13

.

Thus, as the jaw cylinder inner end part

11

and jaw cylinder outer end part

12

rotate in opposite directions on the jaw cylinder core part

13

, so do the fixed jaws J

13

and movable jaws J

12

which are supported respectively on the jaw cylinder inner and outer end parts

11

and

12

. The spacing between the jaws J

12

and J

13

has thus been readjusted and optimized for the current press speed, for the current numbers of webs being processed jointly, and for the current thickness of paper in use.

Referring to

FIG. 8

again, the jaw spacing pulse generator

71

in the form of an incremental, bidirectional rotary encoder will put out a series of jaw spacing pulses indicative of the revolutions of the stepper motor

31

. The arithmetic unit

72

will respond to each incoming jaw spacing pulse by adding or subtracting one to or from the count that has preexisted at the start of the current jaw spacing adjustment routine. The arithmetic unit

72

will proceed to compute from the modified pulse count the actual jaw spacing that has been readjusted as above, and deliver to the jaw spacing adjustment signal generator

91

the jaw spacing signal suggestive of that actual jaw spacing. The jaw spacing adjustment signal generator

91

will again compare the actual jaw spacing with the desired jaw spacing. The same cycle of operation will be repeated if the result of the comparison exceeds the preset limit, until the difference falls below the limit.

Notwithstanding the foregoing detailed disclosure it is not desired that the present invention be limited by the exact showing of the appended drawings or by the description thereof. For example, the input device

100

,

FIG. 8

, will be unnecessary for those printing press systems in which only one web or only one preselected number of webs are to be processed and in which paper of only one known thickness is always to be used. The speed- and thickness-dependent Jaw Spacing Table above will then be modified and simplified, all that has to be stored on the memory

92

in that case being the desired jaw spacings at the various rates of signature production. Furthermore, as indicated by the dashed outline in

FIG. 8

, the press speed pulse counter

52

of the press speed circuit

50

, the arithmetic unit

72

of the jaw spacing circuit

70

, and the jaw spacing adjustment signal generator

91

and memory

92

of the jaw spacing adjustment circuit

90

may be integrated into one electronic processing unit C.

All these and other modifications, alterations and adaptations of the illustrated embodiment are intended in the foregoing disclosure. It is therefore appropriate that the invention be construed broadly and in a manner consistent with the fair meaning or proper scope of the claims which follow.

Number	Name	Date	Kind
5037365	Breton	Aug 1991	A
5405127	Welborn	Apr 1995	A
5571069	Shah	Nov 1996	A
5847177	Sangokoya et al.	Dec 1998	A
6082724	Kahlig et al.	Jul 2000	A
6273313	Noll et al.	Aug 2001	B1
6279890	Tomczak	Aug 2001	B1
6511409	Hachiya et al.	Jan 2003	B2
6514188	Kostiza	Feb 2003	B2

Printing-speed-responsive jaw spacing adjustment system for a jaw cylinder at the folding station of a web-fed printing press

Information

Patent Number

Date Filed

Date Issued

Inventors

Original Assignees

Examiners

Agents

CPC

US Classifications

Field of Search

US

International Classifications

Abstract

Description

Claims

Priority Claims (1)

US Referenced Citations (9)

Foreign Referenced Citations (1)