US3355122A

US3355122A - Web roll stand

Info

Publication number: US3355122A
Application number: US519847A
Authority: US
Inventors: Robert B Thatcher
Original assignee: Chandler and Price Co
Current assignee: Chandler and Price Co
Priority date: 1966-01-11
Filing date: 1966-01-11
Publication date: 1967-11-28
Anticipated expiration: 1984-11-28

Description

R. B. THATCHER WEB ROLL STAND Nov. 28, 1967 2 Sheets-Sheet 1 Filed Jan. 11, 1966 INVENTOR ROBERT 8. THA TCHER ATTORNEYS Nov. 28, 1967 R. B. THATCHER WEB ROLL STAND 2 Sheets-Sheet 2 Filed Jan. 11, 1966 INVENTOR ROBERT E. THATCHER ATTORNEYS ABSTRACT OF THE DISCLOSURE A web roll stand having particular utility in printing presses wherein the web is trained about a pendantly mounted sensing roll which is operatively connected to a lever pivoted on one of a pair of clamp type brake shoes with such lever engaging a pin operative to move the brake shoes apart to vary the braking pressure below a preset maximum.

This invention relates generally as indicated to a web roll stand and more particularly to such roll stand incorporating an improved Web roll braking mechanism.

Web roll stands for printing presses and the like usually incorporate a web tension responsive brake mechanism for the roll which conventionally utilize complex linkages connected to sensing rolls. Moreover, on many conventional web brake mechanisms, quick changes in the speed of the web may cause the brake to tighten actually stopping the roll and thereby increasing the possibility of web breakage. Printing press brake mechanisms must also be highly sensitive since anything affecting the speed of the web will, of course, change the tension on the web and the relatively massive web rolls must react accordingly. With the present invention the desired web tension may be preset and when the web becomes tighter than the original setting, the tension sensing roll will release or open the mechanism, but such mechanism cannot exert more pressure or close beyond its original preset position.

It is accordingly a principal object of the present invention to provide a web roll stand incorporating a web roll brake which is highly sensitive yet of a simplified construction.

A further principal object is the provision of a web roll brake mechanism wherein the brake cannot exert more pressure or close beyond its original preset condition.

Another object is the provision of a web roll brake mechanism wherein the sensing roll may be mounted for substantially free pendant swinging movement.

Yet another object is the provision of a web roll brake mechanism incorporating a lever and push rod on one brake shoe connected to the sensing roll operative to open the brake mechanism in response to tension variations beyond its original setting.

A still further object is the provision of a web roll brake mechanism which can readily be released from the brake drum to facilitate the replacement of rolls.

Other. objects and advantages of the present invention will become apparent as the following description proceeds.

To the accomplishment of the foregoing and related ends,- the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawei d S ate ing setting forth in detail a certain illustrative embodiment of the invention, this being indicative, however, of but one of the various ways in which the principles of the invention may be employed.

In said annexed drawing: v 7

FIG. 1 is a side elevation of a roll stand in accordance with the present invention mounted on a web press-shown in phantom lines; 7

FIG. 2 is an enlarged side elevation of the brake mechanism ofthe roll stand;

FIG. 3 is an end elevation of such brake mechanism taken substantially from the line 3 3 of FIG. 2;

FIG. 4 is a fragmentary view similar to FIG. 2 illustrating the manner in which the brakemechanism separates to permit roll changes; and

FIG. -5 is a fragmentary perspective view of the web roll brake mechanism of the present invention.

Referring now to such'annexed drawings and more particularly to FIG. 1, the web roll stand is illustrated at 1 and may comprise a base 2 provided with structural colurnns Sand 4 on each side. Such columns are joined at the top by structural member 5 and near the bottom by structural member 6. Pairs of supports 8 are provided at the top'of'the column 3 projecting rearwardly thereof forthe shaft 9 of a top web roll 10. Closer to the bottom, pairs of supports 11 are provided each supported by a gusset 12 for the shaft 13 of lower web roll 14.

The web 16 being fed from the roll 10 passes about a sensing roll 17 pendantly mounted on arms 18 pivoted at 19 to the column 4 and then about an idler roll 20 journalled in the column 3 and from there passes to printing assembly 21 stacked on top of printing assembly 22. The web 23 being fed from the roll 14 passes in like manner about sensing roll 24 and idler roll 25 and then into the lower printing assembly 22. From the printing assemblies 21 and 22 the webs then pass to folding unit 26. The printing assemblies and the folder unit are mounted on a common frame or base 27 and include a top frame 28 to which the roll stand 1 may readily be secured or removed.

The sensing roll 24 is like the roll 17 pendantly mounted on arms 29 pivoted at 30 to the column 4 and for each roll unit a rod 31 interconnects the shaft or pivot 30 with the brake unit shown generally at 32. The sensing rolls, connecting rods and brake units for the top and

bottom rolls

10 and 14, respectively, may be substantially identical in form and accordingly only the bottom unit will be described in detail. It will, of course, be appreciated that a roll stand using a single roll or more than the two rolls illustrated may readily be employed. 7

Referring now to FIGS. 2, 3 and 5 it will be seen that the shaft 13 of the roll 14 is provided with a brake drum or pulley 34 having a hub 35 which may be secured to the shaft in a manner to prevent "relative rotation as by the key illustrated; The shaft 13 is supported simply on saddle bearing surfaces 36 on the supports 11 projecting from the column 3. The drum 34 is provided with a V- shape groove 37 which receives

brake shoes

38 and 39 of complementary shape supported on the interior of semicircular

brake shoe holders

40 and 41, respectively. Such brake shoes may be provided with wood or like material linings operative frictionally to engage and thus grip the V- shape groove in the brake drum. 7

The brake shoe helders- 40 and 41 are pivoted together on shaft 43 Vertically beiiath the shaft 13 and as seen more clearly in FIG. 3, such shaft includes an inner threaded portion 44 threaded in nut 45 secured to the frame projection 11. The outer end of the shaft 43 is provided with a hand wheel 46 by means of which such shaft can be rotated. The brake holder 40 may be bifurcated at its lower end to straddle a tongue portion of the brake holder 41 and On each side of such brake holders at the shaft 43,

collars

47 and 48 may be secured to such shaft to provide a trap unit. The brake shoe holders are in this manner confined for longitudinal movement with the shaft 43 which can be obtained by rotating the hand wheel 46. Thus, alignment of the entire brake assembly including the roll shaft 13 and the web 23 may be obtained simply by rotating the hand wheel 46.

As perhaps best seen in FIG. 5, the top of the brake shoe holder 40 is provided with a U-shape slot 50 adapted freely to receive rod 51 threaded as indicated at 52 at one end and provided with an eye 53 at the other. A knob 54 is threaded on the projecting end of the rod and a compression spring 55 extends between the knob and a pressure washer 56. The pressure washer 56 is, of course, of a diameter sutficient to straddle the slot 50. The eye 53 is pivoted to pin 57 extending through slot 58 in the upper end of brake shoe holder 41.

In the position shown in FIG. 5 the two brake shoe holders or halves are clamped together by the pressure of the spring 55 and such pressure may be controlled or preset by adjustment of the knob 54 on the threaded end portion 52 of the rod 51. In this manner the maximum brake pressure can be preset to obtain maximum web tension and the brake cannot exert more pressure or close beyond this preset condition.

To separate the brake shoe holders or

halves

40 and 41 beyond their original preset braking position, there is provided a release lever 60 pivotally connected at 61 at its lower end to rod 31 and just short of the top of the lever to holder 41 by pin 62. The release lever 60 may be journalled on such pin 62 by means of needle or like bearings and such pin extends through slot 63 provided by the

projections

64 and 65 on the exterior of the brake shoe holder 41. The lever 60 is provided with a dogleg or bend 66 and conforms fairly closely to the exterior of the holder 41. The upper end of the lever 60 projects a short distance above the

projections

64 and 65 and engages but is not connected to release pin or rod 68 which extends through and loosely fits in bore 69 (FIG. 2) in the top portion of the holder 41 directly beneath the slot 58. The release pin 68 may be provided with rounded ends with one end engaging the upward projection 70 of the release lever 60 and the opposite end engaging stop button 71 threaded in tapped aperture 72 in the holder 40 directly beneath the slot 50. The button 71 may be provided with a slotted end so that it can be adjusted in the tapped aperture 72 by means of a screwdriver and the like. The adjustment of the button 71 controls the presence or absence of any play between the lever projection 70, the pin 68 and such button and may be employed to compensate for wear.

The operation of the lever 60 is obtained by the rod connection 31 which as seen in FIG. 2 is threadedly adjustably connected to spherical bearing

units

75 and 76 and at the end opposite the pivot 61, pivot 77 extending through spacer 78 into the upper projection 79 of bell crank 80 secured to the shaft or pivot 30. The forwardly extending projection 81 of such bell crank is pin con- .nected to eye 82 of rod 83 extending through bracket 84 secured to the column frame 4. The upper end of the rod 83 is provided with a nut 85 threaded thereon and a compression spring 86 extends between the nut and bracket urging the rod 83 upwardly and thus the shaft 30 in a counterclockwise direction as viewed in FIG. 2.

Sensing roll 24 is journalled onshaft 87 secured to the lower ends of the arms 29 which are in turn secured to clamps 88 held by clamp screws 89 to the shaft 30. The Sensing roll 24 is thus pendantly mounted on the arms 29 directly beneath the shaft 30 and it will be seen that the sensing roll will because of its own weight tend to move to the full line position shown in FIG. 2.

In operation as the tension of the web 23 becomes tighter, the sensing roll 24 will move to the phantom line positions shown at 91 or 92 pivoting the haft 30 against the pressure of spring 86 moving the rod 31 to the right as seen in FIG. 2 and pivoting the lever 60 about the pivot 62 in a counterclockwise direction to cause the upper projection 70 thereof to push release pin 68 against the adjustable button 71 causing the

brake shoe holders

40 and 41 to separate against the pressure of spring 55. Because of the ratio of the distances between the center of the sensing roll 24, the pivot 30 and the pivot 77 as well as the ratio of the distances between the

pivots

61, 62 and the point of engagement between the upper projection 70 of the lever 66 and the release pin 68, it can be seen that a substantial mechanical advantage is obtained. It is also apparent that substantial movement of the sensing roll 24 will obtain but a relatively small movement of separation of the brake shoes but sufficient to obtain the desired brake control. In the illustrated embodiment the ratio of moment arms produced by the lever 60 is approximately 9:1 while the ratio of moments in the sensing roll support arms 29 is approximately 5: 1.

Referring now to FIG. 4 it can be seen that the proximity of the

pivots

43 and 61 permits the

brake shoe holders

40 and 41 to be separated simply by pivoting the rod 51 in a clockwise direction about the pivot 57 and permitting the holders to fall apart or separate pivoting in opposite directions about the shaft 43. A new web roll may then simply be set in place in the saddle bearings on the supports 11 and the brake shoe holders may then be enclosed about the drum 34 and the rod 51 pivoted back into the slot 50 to hold the brake shoe halves together at the desired force set by the knob 54. The rod 31 in this manner does not have to be disconnected and the replacement of web rolls becomes an extremely simplified procedure.

It can now be seen that there is provided a highly sensitive yet simplified web brake mechanism having positive tension control. The setting of the tension control by means of the knob 54 provides the desired web tension and when the web becomes more taut than the original setting, the sensing roll 24 will release or open the brake mechanism, but in no manner can exert more pressure or close the brake beyond its original preset position. Lateral positioning of the web is controlled by the knob 46 adjusting both the brake mechanism and the web roll laterally and when a new roll is required, the brake shoes are opened simply by releasing the tension control knob 54 and lifting the rod 51 from the slot 50 to permit the brake shoes to fall apart away from the brake drum.

Other modes of applying the principles of the invention may be employed, change being made as regards the details described, provided the features stated in any of the following claims or the equivalent of such be employed.

I, therefore, particularly point out and distinctly claim as my invention:

1. A roll stand for web rolls and the like comprising a web roll shaft support, a brake drum mounted on such web roll shaft, a pair of brake shoes mounted on holders pivoted together beneath such shaft, means operative yieldingly to hold said holders together about said drum to exert a predetermined maximum braking pressure thereon, and means responsive to variations of tension on the web payed from such roll instantaneously to vary such braking pressure below the predetermined maximum by prying said holders apart.

2. A roll stand as set forth in claim 1 wherein said last-mentioned means comprises a sensing roll in engagement with such web, and mechanical advantage link means interconnecting said sensing roll and said brake .shoe holders operative resiliently to force said holders apart in response to increased tension on such Web.

3. A roll stand as set forth in claim 2 wherein said mechanical advantage link means includes a pair of arms pendantly supporting said sensing roll and a release lever pivoted to one of said holders.

4. A roll stand as set forth in claim 3 including a release pin projecting freely through one of said holders and engaging the opposite holder, said release lever being in engagement with said release pin.

5. A roll stand as set forth in claim 3 including a pivot shaft connected to said arms, and a rod interconnecting said pivot shaft and said release lever.

6. A roll stand as set forth in claim 3 including spring means operative to urge said sensing roll in a direction to obtain such predetermined braking pressure.

7. A roll stand as set forth in claim 1 wherein said holders are coaxially pivoted on an axially adjustable shaft beneath such roll shaft, a trap unit confining such holders to such pivot shaft for axial movement therewith, and means operative axially to move said shaft laterally to adjust said brake shoes and thus such web roll.

8. A roll stand for web rolls and the like comprising a web roll shaft support, a brake drum mounted on such web roll shaft, a pair of brake shoes mounted on holders pivoted together beneath such shaft, means operative yieldingly to hold said holders together about said drum to exert a predetermined maximum braking pressure thereon, and means responsive to variations of tension on the web payed from such roll to vary such braking pressure below the predetermined maximum; said lastmentioned means comprising a sensing roll in engagement with such web, mechanical advantage link means interconnecting said sensing roll and said brake shoe holders operative resiliently to force said holders apart in response to increased tension on such web, said mechanical advantage link means including a pair of arms pendantly supporting said sensing roll and a release lever pivoted to one of said holders, a release pin projecting freely through one of said holders and engaging the opposite holder, said release lever being in engagement with said release pin, and an adjustable button on said opposite holder engaged by said release pin.

References Cited UNITED STATES PATENTS 1,829,337 10/1931 Brueshaber 242-75.43 1,987,329 1/1935 Fankboner -24275.43 2,972,452 2/ 1961 Aumann 242-75.43

FRANK I COHEN, Primary Examiner.

N. L. MINTZ, Assistant Examiner.

Claims

1. A ROLL STAND FOR WEB ROLLS AND THE LIKE COMPRISING A WEB ROLL SHAFT SUPPORT, A BRAKE DRUM MOUNTED ON SUCH WEB ROLL SHAFT, A PAIR OF BRAKE SHOES MOUNTED ON HOLDERS PIVOTED TOGETHER BENEATH SUCH SHAFT, MEANS OPERATIVE YIELDINGLY TO HOLD SAID HOLDERS TOGETHER ABOUT SAID DRUM IN EXERT A PREDETERMINED MAXIMUM BRAKING PRESSURE THEREON, AND MEANS RESPONSIVE TO VARIATIONS OF TENSION ON THE WEB PAYED FROM SUCH ROLL INSTANTANEOUSLY TO VARY SUCH BRAKING PRESSURE BELOW THE PREDETERMINED MAXIMUM BY PRYING SUCH HOLDERS APART.