US3051363A - Guide for a traveling vertical web - Google Patents

Description

Aug. 28, 1962 Filed Sept. 8, 1960 H. W. BROWN GUIDE FOR A TRAVELING VERTICAL WEB 2 Sheets-Sheet 1 INVENTOR.

1962 H. w. BROWN 3,051,363

GUIDE FOR A TRAVELING VERTICAL WEB Filed Sept. 8, 1960 2 Sheets-Sheet 2 IN V EN TOR.

BY 60 ry, Dav/2072 d 5 a Pie? United States Patent Office 3,851,363 Patented Aug. 28, 1962 3 051 363 GUIDE FOR A TRAlJEliING VERTICAL WEB Harry W. Brown, Appleton, Wis, assignor to Gilbert &

Nash Company, Menasha, Wis, a corporation of Wiscousin Filed Sept. 8, 1960, Ser. No. 54,995 7 Claims. (Cl. 22623) This invention relates to improvements in a guiding mechanism for paper forming wires or screens, blankets or other traveling webs, and refers particularly to a device for sensing misaligned movement of the web, the sensing mechanism functioning to actuate an aligning mechanism which in response to said actuation realigns the web.

More particularly, the invention relates to a guiding mechanism of the type described by Wendshuh and Lamon in United States Patent No. 2,877,013, issued on March 10, 1959.

One of the important features of the present invention resides in a mechanism which, in response to a relatively small amount of work exercised by a misaligned generally vertical web upon a sensing device, results in the exercise of a relatively large amount of Work by a web-realigning mechanism in restoring the web to its properly aligned path.

Another important feature of the invention resides in the provision of a pneumatic web-aligning mechanism which is prevented from making continuous abrupt changes, or hunting, by the provision of a hydraulic damper.

A further important feature of the invention resides in a sensing mechanism and valve mechanism associated with the web realigning mechanism which when said realigning mechanism moves properly to align the web simultaneously acts to close the actuating valve which the sensing mechanism previously opened to initiate the realigning movement.

Still another significant feature of the present invention is the elimination of the pilot valves employed in the device of the above-identified patent.

Also of major importance in the present invention is the provision of means, in conjunction with a guiding mechanism for a generally vertically traveling web, that nullify the eifects of gravity.

An additional important feature of the present invention resides in a rugged and sturdy mechanism of the class described which is simple in construction and operation.

Other objects, advantages, and features of the invention will become apparent from the following detailed description and accompanying drawings in which:

FIG. 1 is an end elevational view of a device embodying the concepts of the present invention;

FIG. 2 is a bottom view of the device shown in FIG. 1 taken along line 2'2 thereof;

FIG. 3 is an enlarged sectional view taken on line 33 of FIG. 1;

FIG. 4 is a sectional view taken along line 44 of FIG. 3 and showing a special 4-way control valve in an equilibrium position;

FIGS. 5 and 6 are sectional views similar to FIG. 4 but illustrating positions of the control valve under dynamic conditions.

The device of the present invention accomplishes the aforesaid desiderata, particularly the nullification of gravitational effects, by virtue of pressure regulating means that function between portions of a movable vertically mounted cylinder, said portions being separated by a fixed piston.

Referring in detail to the drawings, 1 indicates a generally vertically traveling web which may comprise a paper forming wire or screen, a traveling blanket or other type of web or belt which it may be desired to maintain in a substantially constant path during its travel. In some conventional types of wire guides, a guide roll is employed to control the lateral movement of web 1 and such a roll 2 is contemplated herein. Roll 2 is disposed transversely to the axis of the web and the web will normally assume a position that brings the longitudinal axis thereof at right angles to the axis of the guide roll. Hence, by inclining the axis of roll 2 in one direction or the other a force is exerted upon the web to move it laterally in a predetermined direction.

The device comprising the present invention is directed to a mechanism which so inclines roll 2 in response to an undesired lateral movement of web 1, such inclination functioning to return the web to its desired path.

Roll 2 is carried upon an axle 3, only one end portion of which is illustrated, the opposite end portion being journaled in a bearing (not shown) which has a degree of freedom to move as the axis of the roll is inclined. Such self-aligning bearings are well known in the art. The illustrated portion of axle 3 is journaled in a self-aligning bearing 4 which is mounted upon a movable carriage 5 which, as will be hereinafter more fully described, functions to move the bearing so as to incline the axis of roll 2 relative to its normal position.

Movable carriage 5 is slidably mounted upon a stationary frame 6 which is secured to a stationary portion of a paper making machine or the like (not shown). The movement of carriage 5 is vertical and substantially parallel to the general direction of travel of web 1; in order to restrain the carriage for movement in this direction, the portion of the carriage that slides on stationary frame 6 may be provided with a groove and the stationary frame with a guide rib that registers with the groove.

Carriage 5 fixedly carries a pair of hollow cylinders 18 and 19 which are disposed vertically and substantially parallel to each other side-by-side within stationary frame 6 which has a box-like structure. Cylinders 18 and 19 are fiuid-tight and are adapted to be moved up-and-down, thereby causing vertical movement of carriage 5.

A piston 24 is positioned in cylinder 18 and is rigidly secured as by locking rings to a shaft 26 which extends through cylinder 18 and projects outwardly at each end through packing glands or the like. Similarly, a piston 28 is positioned in cylinder 19 and is rigidly mounted as by locking rings to a shaft 30 which extends through the cylinder and projects outwardly at each end through packing glands or the like.

Cylinders 18 and 19, as hereinbefore stated, are carried by movable carriage 5. Hence, cylinders 18 and 19 are disposed within stationary frame 6 in desired position therein. The arrangement is such that when air under pressure is introduced into cylinder 18 on one or the other side of piston 24, cylinder 18 will be moved. That is, piston 24 is stationary being fixedly locked to: stationary frame 6, but cylinder 18 is movable relative there to. Of course when cylinder 18 moves, carriage 5 moves therewith and hence the carriage moves relative to stationary frame 6. In this fashion by the selective introduction of air under pressure to cylinder 18, the end of shaft 3 within bearing 4 may be moved relative to stationary frame 6 of the machine and relative to the opposite bearing in Which the shaft is also journaled, movement taking place substantially parallel to the longitudinal axis of web 1.

Piston 28 is provided with a bleed hole not seen in the drawings. Cylinder 19 on both sides of piston 28 is filled with a liquid and the bodies of liquid on each side of the piston 2-8 are in communication through the bleed hole. When air under pressure is introduced into cylinder 18, causing cylinder 18 to move in one direc- 3 tion or the other, such movement is damped by the transfer of liquid through the bleed hole from one side of piston 28 to the other side thereof within cylinder 19. Accordingly, abrupt movements of carriage are avoided and, as will be hereinafter more fully described, hunting is substantially eliminated.

To detect lateral movement of web 1 from its normal position, a sensing element is employed, such sensing element comprising a feeler in the form of a palm 37. Palm 37 is carried by an arm 40, the latter being carried by a rotatable shaft or pin 41 journaled in a bearing 42. Bearing 42 is carried at the upper end of a stationary bracket '43 which in turn is secured to a supporting bracket 44 that is mounted upon the stationary portion of the machine. Brackets 43 and 44 are slotted, and locking means having a hand wheel 47 for its convenient manipulation function to adjustably secure bracket 43 to bracket 44. Thus, palm 37 is free to swing or pivot about arm 40 to dispose its surface in contacting alignment with the adjacent edge of web 1, such contact being effected by means subsequently disclosed.

A link 50 is connected fixedly to the end of pin 41 that is remote from bracket 43. Link 50, at the end thereof remote from pin 41, is flattened and is provided with an eye in which a pin 53, carried by a sleeve 54, is pivotally positioned. Sleeve 54 is mounted upon one end of a connecting link 55, a coupler 56 being interposed in the length thereof for varying the effective length of link 55.

At its opposite end, link 55 is pivotally connected to an arm 57 which, in turn is rigidly mounted upon a shaft 58 journaled in bearings formed integrally with stationary bracket 44. An arm 60 is rigidly secured to the end portion of shaft 58 that is remote from arm 57, and the end of arm 61 that is remote from shaft 58 is pivotally connected to one end of a link 61. A turnbuckle may be interposed in link 61 to vary the effective length thereof. A block 62 is mounted asymmetrically on shaft 58, the force of gravity acting on block 62 to generate a torque on shaft 58 in such a sense that palm 37 is constantly urged into contact with the edge of web 1. As viewed in FIG. 1, block 62 applies a clockwise torque to shaft 58, shaft 58 seeks to move the upper end of arm 57 and link 55 to the right, and link 55 causes sleeve 54, pin 53, and link 50 to exert a torque on pin 41 that urges palm 37 into contact with web 1.

A supporting plate 63 is secured to the movable carriage by screws 64 and carries a four-way valve 65 that is secured to the plate. The structural features of valve 65 will be hereinafter more fully described, but in general it is manipulated by the rotation of a valve control shaft 67. A block 68 is mounted upon valve control shaft 67 and carries an arm 69 which is pivotally connected to link 61.

As viewed in FIG. 1, valve 65 communicates with the upper portion of cylinder 18 via flexible pipe means 72. Valve 65 also communicates with the lower portion of cylinder 18 successively through a nipple 73, a pressure regulator 74, and flexible pipe means 75. The upper and lower portions of cylinder 18, as stated before, are divided 'by a piston 24 which is fixedly carried by stationary frame 6. Valve 65, in addition to being connected to the upper and lower portions of cylinder 18, is also connected to a source of air (not shown) under pressure by a pipe 80; a vent pipe 81 is also connected to valve 65.

In the normal position of the device, that is when web 1 moves along the desired path, valve 65 is closed as shown in FIG. 4 and pipe 80 is connected to both pipe 72 and nipple 73, and thus to both the upper and lower portions of cylinder 18. However, when web 1 deviates in either lateral direction from its normal path, palm 37 is either moved by the web edge or is caused to follow the web edge thereby moving the palm linkage; as a result, arm 69 is moved to turn shaft 67 of valve 65 and cylinder 18 is thereby vented on one or the other side of piston 24 as will be hereinafter more fully described.

The construction of valve 65 is diagrammatically shown in FIGS. 3, 4, 5 and 6, wherein 89 designates a valve body which is provided with a cylindrical bore 90. A substantially prismatic rotor 91 having truncated edges is fixedly mounted upon valve control shaft 67 and is rotatably positioned in bore 90, the valve control shaft being connected to rot-ate the rotor in response to movement of the palm linkage. Valve body 89 is provided with four ports 92, 93, 94 and 95, and as shown in FIG. 4, port 92 is connected to air inlet pipe 30, port 93 is connected to flexible pipe means 72, port 94 is connected to nipple 73, and port 95 is connected to vent pipe 81. Rotor 91 is provided with a transverse bore 97 and due to the prismatic geometry of the rotor and the cylindrical geometry of bore 90, sectoral spaces 98, 99, and are formed therebetween.

In FIG. 4, the equilibrium position of rotor 91 is illustrated. It will be noted that in the equilibrium position, vent port 95 is closed by one of the truncated edges of rotor 91, and both ports 93 and 94 are in communication with inlet port 92. Under these static conditions, cylinder 18 and piston 24 will not be moved relative to one another.

In FIG. 5 rotor 91 has been rotated by the movement of the palm linkage due to a lateral shifting of web 1 in a predetermined direction. Rotor 91 in the tilted position shown in FIG. 5 causes one of the truncated edges of rotor 91 to uncover vent port 95, whereupon sectoral space 106 communicates with sectoral space 98 and vent port 95. In this position it will be noted that port 93 remains in communication with inlet port 92, whereas port 94 is disconnected from inlet port 92. Under these conditions, the lower portion of cylinder 18 will be vented and cylinder 18 will move upwardly causing carriage 5 to do likewise, piston 24 remaining fixed in position at all times.

In FIG. 6, rotor 91 has been rotated in a sense opposite to the sense experienced in FIG. 5; this reversal in sense of rotation is the result of a lateral shifting of web 1 from its desired path in a direction counter to the lateral shifting indicated by FIG. 5. Under the conditions associated with FIG. 6, vent port 95 has been uncovered by one of the truncated edges of rotor 91 thereby permitting communication between sectoral space 98 and vent port 95 via bore 97; inlet port 92 remains in communication with port 94 and consequently with the lower portion of cylinder 18 through pressure regulator 74; and the upper portion of cylinder '18 is vented via port 93, sectoral space 98, bore 97, and vent port 95. Thus cylinder 18 and carriage 5 are moved downwardly, piston 24 remaining fixed in position at all times.

As has been hereinbefore described, these movements are damped by cylinder 19 moving relative to piston 28 and comprise relatively slow controlled movements. As cylinders 18 and .19 move, carriage 5 moves and hence bearing 4 shifts the end of shaft 3 .to cant or incline roll 2 relative to the web 1. It can readily be seen that when the cylinders and movable carriage thus move, valve 65 moves therewith and consequently although the palm linkage functioned to initiate the movement, the movement of the valve relative to the linkage functions to return rotor 91 to its normal position. Hence, there is no tendency for the device to perform an over-correction, the device having a self-zeroing action.

It is understood that a single source of air pressure is supplied to inlet port 92, whereupon rotor 91 of valve 65 may supply both ports 93 and 94 simultaneously with said air pressure via sectoral space 99 as seen in FIG. 4, or either of said ports 93 or 94 may be supplied with air pressure exclusively, as depicted by FIGS. 5 and 6.

In any case, air pressure supplied to the upper portion of cylinder 18 seeks to move the cylinder upwardly, while air pressure supplied to the lower portion of cylinder 18 seeks to move the cylinder downwardly. Since air of the same pressure is supplied to each port 93 and 94 under the equilibrium conditions prevailing in FIG. 4, it might be assumed that piston 24 would be disposed midway within cylinder 18 and that any lateral shifting of generally vertical web 1 would cause the desired correction to take place in the manner previously related. However, due to the mass of web 1, roll 2, shaft 3, and carriage 5, a substantial gravitational force acts on cylinder 18 to move the cylinder downwardly, i.e., in opposition to the air pressure supplied to the upper portion of cylinder 13 and in concert with the air pressure supplied to the lower portion of cylinder 18. The net result under equilibrium conditions of this pressure imbalance that is caused by the mass of web 1, roll 2, shaft 3, and carriage 5 would seem to be the movement of cylinder 18 downwardly until piston 24 resided within the uppermost end of cylinder 18; however, such an extreme would not be reached, since cylinder 18 in moving downwardly could cause web It to become misaligned and a motion to correct would be transferred to rotor 91. The correction dictated would take place due to the severance in communication between the upper and lower portions of cylinder 18 caused by the changes in position of rotor 91 and sectoral space 99; however, as soon as the correction occurred, a rotor 91 would again assume the equilibrium position shown in FIG. 4, a pressure imbalance would be reestablished, and the correction cycle would be experienced anew. The aforesaid pattern would be repeated ad infinitum whenever the mechanism of Wendshuh and Lamon, hereinbefore identified, is sought to be utilized for vertical applications, thus preventing web 1 from ever assuming a relatively stable horizontal position.

The device of the present invention circumvents the above-described inherent malfunction of the Wendshuh and Lamon mechanism by providing pressure regulator 74 between port 94 of valve 65 and the lower portion of cylinder 18, i.e., between nipple 73 and flexible pipe means 75. Pressure regulator 74 maintains a pressure differential between port 94 of valve 65 and the lower portion of cylinder 18, such pressure differential being exactly equal to the pressure imbalance caused by the mass of web 1, roll 2, shaft 3, and carriage 5. Thus the air pressure supplied to the upper portion of cylinder 18 in FIG. 1 by the source of air pressure will be substantially greater than the air pressure supplied to the lower portion of cylinder 18 due to pressure regulator 74. However, the effective result of this implanted pressure differential is the disposition of piston 24 midway within cylinder 18 in a stable nonoscillatory state until such time as web 1 becomes misaligned, whereupon a true error movement will be transferred to rotor 91 to trigger a nontrivial correction action.

Typical pressures for the device of the present invention may be 60 p.s.i. at inlet port 92 and in the upper portion of cylinder 18, and 20 p.s.i. in the lower portion of cylinder 18, pressure regulator 74 thus being set to maintain a differential of 40 p.s.i. The differential pressure to be maintained by pressure regulator 74- is easily derived by dividing the gravitational force on cylinder 18 due to web 1, roll 2, shaft 3, and carriage 5 (including cylinder 18) by the face area of piston 24. In practice, pressure regulator 74 is set in the proper manner by positioning palm 37 as desired with valve 65 as shown in FIG. 4, and then manipulating the pressure regulator until piston 24 is disposed midway within cylinder 18.

Pressure regulator 74 is a conventional element; therefore, no detailed description or illustration of the pressure regulator is provided herein.

A conventional four-way valve may be employed as valve 65. However, in view of the excellent characteristics of the valve illustrated in FIGS. 3, 4, 5, and 6, this type of valve is preferred.

One of the important advantages of the invention resides in the fact that palm 37 can be made to bear relatively gently upon the edge of web 1 and that valve 65 can be moved very easily by the movement of the palm. Hence, the force exerted by the palm upon the edge of web 1 will not tend to wear the Web unduly. The valving arrangement embodied in the present invention resembles the operation of a conventional relay wherein by the exercise or release of a relatively small quantity of energy, a large quantity of energy may be proportionately controlled.

It is to be understood that the device comprising the present invention may be employed in guiding paperforming wires and screens, traveling blankets, belts and the like all of which are referred to as webs. For purposes of convenience and clarity, four-way valve 65, which functions as a control valve, is referred to in the appended claims as a control valve.

In view of the fact that many of the components of the present device are similar to those used in conventional web or wire guides, it is to be understood that the present device may be modified to conform with different types of conventional equipment and hence it is not intended that the present invention be limited to the exact details shown and described except as necessitated by the appended claims.

I claim:

1. In a web guiding device wherein a guide roll in surface contact with a traveling web is shifted in response to the movement of a feeler palm in contact with the lateral edge of the web, the combination of a stationary frame, a carriage movably mounted on said frame for carrying one end of said guide roll, a control valve mounted on said carriage, a pressure regulator, pipe means connecting said control valve to a source of air under pressure, a cylinder rigidly mounted on said carriage and movable relative to said frame, a piston carried in said cylinder and fixedly mounted relative to said frame, pipe means connecting said control valve to one end of said cylinder, pipe means connecting said control valve to said pressure regulator, pipe means. connecting said pressure regulator to theother end of said cylinder, and means for connecting said control valve to said palm to selectively actuate said control valve in response to movement of said palm.

2. In a web guiding device wherein a guide roll in surface contact with a traveling web is shifted in response to the movement of a feeler palm in contact with the lateral edge of the web, the combination of a stationary frame, a carriage movably mounted on said frame for carrying one end of said guide roll, a control valve, means connecting said control valve to a source of air under pressure, a cylinder rigidly mounted on said carriage and movable generally vertically relative to said frame, a piston carried in said cylinder and fixedly mounted relative to said frame, means connecting said control valve to the opposite ends of said cylinder and including means normally producing a differential in air pressure between the opposite ends of said cylinder to nullify the effects of gravity on said carriage, and means for connecting said control valve to said palm to selectively actuate said control valve in response to movement of said palm.

3. In a web guiding device wherein a guide roll in surface contact with a traveling web is shifted in response to the movement of a feeler palm in contact with the lateral edge of the web, the combination of a stationary frame, a carriage movably mounted on said frame for carrying one end of said guide roll, a control valve mounted on said carriage, a pressure regulator, pipe means connecting said control valve to a source of gaseous fluid under pressure, a cylinder rigidly mounted on said carriage and movable relative to said frame, a piston carried in said cylinder and fixedly mounted relative to said frame, hydraulic means carried by said carriage for damping the movement of said carriage, pipe means connecting said control valve to one end of said cylinder to pass air under relatively high pressure thereto, pipe means connecting said control valve to said pressure regulator, pipe means connecting said pressure regulator to the other end of said cylinder to pass air under relatively low pressure thereto, and means for connecting said control valve to said palm to actuate said control valve selectively to pass air under pressure to said cylinder ends in response to movement of said palm.

4. In a web guiding device wherein a guide roll in surface contact vvith a traveling Web is shifted in response to the movement of a feeler palm in contact with the lateral edge of the web, the combination of a stationary frame, a carriage movably mounted on said frame for carrying one end of said guide roll, a four-Way control valve mounted on said carriage, pipe means connecting said control valve to a source of air under relatively high pressure, a pressure regulator, a cylinder rigidly mounted on said carriage and movable relative to said frame, a piston carried in said cylinder and fixedly mounted relative to said frame, pipe means connecting said control valve to one end of said cylinder to pass air under relatively high pressure thereto, pipe means connecting said control valve to said pressure regulator, separate means connecting said control valve to the atmosphere, pipe means connecting said pressure regulator to the other end of said cylinder to selectively pass air under relatively low pressure thereto, and link means for connecting said control valve to said palm to selectively actuate said control valve in response to movement of said palm.

5. In a web guiding device wherein a guide roll in surface contact with a traveling generally vertical web is shifted in response to the movement of a feeler palm in contact with the lateral edge of the web, the combination of a stationary frame, a carriage movably mounted on said frame for carrying one end of said guide roll, a control valve mounted on said carriage, pipe means connecting said control valve to a source of air under relatively high pressure, a pressure regulator, a cylinder rigidly mounted on said carriage and movable relative to said frame, a piston carried in said cylinder and fixedly mounted relative to said frame, pipe means connecting said control valve to one end of said cylinder to pass air under relatively high pressure thereto, pipe means connecting said control valve to said pressure regulator, pipe means connecting said pressure regulator to the other end of said cylinder to pass air under relatively low pressure thereto, said control valve normally atfording communication between said one cylinder end, said pressure regulator, and said source of air under relatively high pressure, and means for connecting said control valve to said palm to selectively actuate said control valve in response to movement of said palm.

6. In a device for guiding a traveling generally vertical web along a substantially constant path comprising a stationary frame for disposition adjacent a traveling Web, a carriage movable upon said frame in a direction generally parallel to the path of travel of said Web, a guide roll for making transverse surface contact with said web, one end of said guide roll being mounted upon said car- 8 riage, a feeler palm carried upon said frame for making following contact with a lateral edge of said web, and means mounted on said carriage and connected to said palm for moving said end of the guide roll in response to the movement of said palm, said means comprising a fluid pressure cylinder carried along a generally vertical axis by said carriage and movable with said carriage generally vertically relative to said frame, a piston disposed fixedly relative to said frame Within said cylinder, a control valve carried by said carriage and connected to said palm for manipulation in response to movement of said palm, a pressure regulator carried by said carriage, means for connecting said control valve to a source of air under pressure, a connection between said control valve and one end of said cylinder, a connection between said control valve and said pressure regulator, a connection between said pressure regulator and the other end of said cylinder, a second cylinder carried by said carrier adjacent to said first-mentioned cylinder, a second piston carried in said second cylinder, and means rigidly connecting said second piston to said frame, said second piston being provided with an opening permitting communication of portions of said second cylinder on each side of said second piston for the passage of liquid carried by said second cylinder when said carriage moves. 7. A device for guiding a traveling generally vertical web along a substantially constant path comprising a stationary frame for disposition adjacent a traveling Web, a carriage movable upon said frame in a direction generally parallel to the path of travel of said web, a guide roll for making transverse surface contact with said web, one end of said guide roll being journaled upon said carriage, a feeler palm carried upon said frame for making following contact with a lateral edge of said Web, means mounted on said carriage and connected to said palm for moving said end of the guide roll in response to the movement of said palm, said means comprising a fluid pressure cylinder carried by said carriage and movable with said carriage relative to said frame, a piston positioned in said cylinder, means rigidly connecting said piston to said frame, a control valve carried by said carriage and connected to said palm for manipulation by said palm in response to its movement, means connecting said control valve to a source of fluid under pressure, a pressure regulator carried by said frame, means connecting said control valve to one end of said cylinder, means connecting said control valve to said pressure regulator, means connecting said pressure regulator to the other end of said cylinder, and link means connecting said control valve and feeler palm.

References Cited in the tile of this patent UNITED STATES PATENTS 2,635,475 Hornbostel Apr. 21, 1953 2.871013 Wendshuh Mar. 10, 1959 2,988,720 Mittag May 31, 1960

Images