US2719463A - Machines for reducing and treating fibrous paper making materials - Google Patents

Description

Oct. 4, 1955 AUG ING AND T REATING ERIALS 4 MACHINES FOR UC FIBROUS PAPER MA Filed Jan.

KING 29,

INIiENTOR. ZQZLIJ BY 7zmm ATTORNEY Unite States Patent MACHINES FOR REDUCING AND TREATING FIBROUS PAPER MAKING MATERIALS Anton J. Hang, Nashua, N. H.

Application January 29, 1954, Serial No. 407,013

16 Claims. (Cl. 92-26) This invention relates to improved methods and apparatus for mechanically working or treating fibrous ma terials, and particularly fibrous materials, such as are commonly employed to produce a pulp stock in the paper making art. It is intended that the expression mechanically working, as employed throughout the specification, may relate to and include broadly various operations dealing with specific treatment of fibrous materials such as, for example, reducing, beating, pulping, hydrating, fibrillating, and the like, as well as to certain combinations of these operations. The present application is a continuation in part of my copending application Ser. No. 201,341, filed December 18, 1950, now Patent No. 2,674,762.

It is an object of the invention to improve methods and apparatus for mechanically working fibrous paper making materials, and through this improved means to otfer to an operator a fluid stream control which will enable him to exert a predescribed uniform treatment of all of the material comprising the fluid stream. Another object is to deal with difiiculties now encountered in treating relatively coarse reject materials, such as kraft knots and sulphite knots, as well as other stringy fibrous bodies as, for example, sliver screen waste, and the like. Still another object of the invention is to provide a method of selectively developing specific fiber properties without unduly modifying dimensional characteristics or other physical aspects of the fibers which should be retained. A further object of the invention is to provide an improved method and apparatus for treating fibrous materials whereby a plurality of conventional treating operations may be combined and carried out in a single machine. Still a further object of the invention is to provide a roller type machine for mechanically working fibrous materials, which machine is of simple and eflicient construction and which is characterized by a special roll retaining structure.

These and other objects and novel features will be more fully understood and appreciated from the following description of a preferred embodiment of the invention selected for purposes of illustration and shown in the accompanying drawings, in which Fig. 1 is a cross-sectional view, partly in elevation, illustrating one form of apparatus of the invention;

Fig. 2 is an end elevational view further illustrating the various working parts of the machine shown in Fig. 1;

Fig. 3 is a vertical, cross-sectional view further illustrating the arrangement of rollers and screw conveyor means employed in the apparatus shown in Figs. 1 and 2;

Fig. 4 is an elevational view of another form of roller which may be employed; and

Fig. 5 is a diagrammatic view of paths of movement of diverted streams of fibrous material.

In accordance with the invention I have discovered improved methods for mechanically working fibrous materials. One important step in the method is to move a stream of fluid fibrous material, including chips, knots, and the like, along a substantially circular path of movemeat so that the material is spread out in the form of a relatively thin circular stream or layer and held against a cylindrical casing by means of centrifugal forces. When thus whirled about at varying speeds, the fluid stream develops strong inertial forces which can be utilized advantageously to uniformly work the material which is carried in the stream.

I make use of these inertial forces by a further step of interposing a series of succeeding conduit forming portions in the path of movement of the circular stream of material. The conduit forming portions are caused to rotate in a controlled manner at varying and different speeds from that of the stream, and these conduit portions preferably are embodied in the form of a screw element cooperating with adjacent surfaces of the cylindrical casing noted to confine the stack in a controlled manner. As a result, the fluid stream as it comes in to contact with the conduit forming portions becomes periodically diverted as a body in directions axially of the cylindrical casing, along distances which are directly proportionate to the speed of rotation of the rotating members to thus furnish a unique and highly uniform control of stock treatment.

In conjunction With this step of diverting the stream periodically I further apply rolling pressure to the fluid stream and in a definite sequential relationship with respect to the axial diverting step. I have determined that I may very advantageously apply this rolling pressure simultaneously at two or more points and, in particular, at two opposite sides of the screw member. In this way the stock is crushed, compressed upon itself, and then almost instantly passed to the screw where it is diverted axially, turned over upon itself, and reformed. While thus turned over upon itself the material is again subjected to crushing pressure and thereafter this cycle is repeated. I find that such an operation may be carried out by a plurality of rolls supported in rolling contact with the cylindrical casing at two separated points. I also find that I may advantageously locate one of the rolls directly in contact with the screw member. Moreover, I can use the bottom roll to increase pressure between the top roll and the cylindrical casing.

In connection with supporting one or more rolls in a revolving casing, as suggested above, I have further devised a special roll mounting by means of which axial displacement of the cylindrical casing may be controlled in a very desirable manner.

in the structure shown in the drawings, Fig. l illustrates one desirable form of apparatus of the invention which is especially suitable for crushing and pulping reject material, such as coarse chips, knots, and the like. As shown in this figure, a revolving cylindrical casing It) is provided for receiving a slurry of chips, knots, or other fibrous substances. This cylindrical. casing 10 is entirely supported on an upper roll member 14 in turn mounted on a shaft 16 journalled in bearings 18 and 20. The latter bearing members are located in end frames 22 and 24, and at one end of shaft 16 is a belt drive 26 operated from a motor 28.

By means of the arrangement described the roll 14 may be driven at varying speeds and the cylindrical casing is revolved with this roll. A slurry of chips, knots, or other stock is normally introduced into the cylindrical casing through an inlet member 30 which communicates with a conical or tapered ring body 32 fitted at one end of the cylindrical casing, as shown in Fig. 1. Stock entering the inlet 36 is fed on to conveyor flights 34 on the shaft 16 and these conveyor flights advance the stock in a direction from left to right, as viewed in Fig. l, finally dumping the material in to the lower section of the revolving casing.

Once the stock has been delivered into the revolving casing, it is immediately picked up and whirled around in a thin substantially circular stream which is held against the inner periphery of the casing by centrifugal forces. Since the cylindrical casing is a relatively heavy steel body, it will be apparent that a considerable crushing force is exerted on chips and knots which are passed between the cylindrical casing and roller 14. It will be further obvious that this crushing action will be repeated in rapid succession, depending, to some extent, upon the speed of rotation of the roll and casing. Stock thus treated may leave the revolving cylindrical casing by means of an outlet 38 provided at the right-hand end of the machine, as viewed in Fig. l.

An important feature of the invention is the combination with the above described structure of the rotating screw referred to above and a second lower roll of similar construction to that of the roll 14. Numeral 48 denotes the rotating screw element and numeral 42 indicates the lower roll (Fig. 3).

The screw as shown in Figs. 1 and 2 has its extremities mounted between the end frames 22 and 24 in a position such that the longitudinal axis of the screw lies in a horizontal plane passing through the longitudinal axis of the revolving casing 10 when the latter member is in a position such as that shown in Figs. 1 and 3. The screw is further positioned in a manner such that its flights are in rolling contact with the periphery of the upper roll 14 so that the flights scrape away fibrous material which seeks to collect on the surfaces of the roll 14, particularly at points where the roll surface is formed with grooves 14a. Also, the screw element is chosen of a diameter such that when the axis of the screw is located, as above described, the flights thereof will lie in very close proximity to the inner periphery of the cylindrical casing 10 without actually coming into contact with it at any point, as may be better seen from an inspection of Fig. 3.

The lower roll 42 is, in accordance with the invention, mounted on a shaft 44, the ends of which are received in bearings 46 and 48. These bearings are vertically adjustable in hydraulic units 50 and 52, illustrated in Fig. 1. At one end of the shaft 44 is fixed a pulley 54 driven by belts 56 and motor 28. A separate motor 4-1 is mounted in a raised position and drives a belt 43 on a pulley 45 to furnish independent driving means for the screw 40 when the rolls 14 and 42 are rotated by means of the motor 28. A circular enclosure plate 58 surrounds the end of the casing 10 at the right-hand side thereof as viewed in Fig. 1 and the enclosure plate has both the shafts l6 and 44, as well as the screw 46), received through openings formed therein.

As best shown in Fig. 3 the roll 42 is located in rolling contact with the inner peripheral surface of the cylindrical casing 10 in a position so chosen that the longitudinal axis of the roll 42 lies in a vertical plane passing through the longitudinal axis of the cylindrical casing 10 and also the axis of the top roll 14. This lower roll 42, in the position described, is adapted to bear against the longitudinal casing with a very considerable force which can, at will, be increased by means of the hydraulic units 50 and 52. it is pointed out that pressure thus exerted on the bottom of the cylindrical casing performs two important functions. it increases the crushing pressure between the cylindrical casing and the bottom roll 42 and simultaneously forces the cylindrical casing against the top roll with increasing pressure intensity to thus augment crushing pressure at this point also.

In a preferred arrangement the upper roll 14, together with the lower roll 42 and the casing 10 are all caused tor-otate in a clockwise direction, as viewed in Fig. 3, while the screw 40 is rotated in a counterclockwise di rection, as viewed in Fig. 3. Also, for an arrangement which involves counterclockwise rotation of the screw 40, as noted, this latter member is preferably constructed so that the flights advance from left to right, as viewed in Fig. 3 and thus constitute righthand flights, as may be better seen in Fig. l.

I have found, in general, that with an organization of parts, as described, and with these parts driven at suitable rotating speeds, I am enabled to carry out a mechanical working of chips and other fibrous materials, in such a way that each constituent part of the circular stream of material can be subjected to precisely the same treatment and in this way there can be achieved a remarkable degree of uniformity in treatment of stock not heretofore realized in the art so far as I am aware.

It will be seen that the flights of the screw cooperate with the peripheral surface of the cylindrical casing to con stantly provide a series of conduit forming portions through which the stream of stock is guided and diverted in directions axially of the cylindrical casing. The step of axially diverting the stream of stock is found to have one exceedingly important aspect. Such a step provides a means of working the stock in a much more uniform manner, as above noted, and this may be attributable to the fact that the screw flights divert substantially all of the stream and the material carried in it at any given point and, in addition, the extent to which any given portion of the stream may be diverted is capable of being controlled within very close limits by varying the speeds of the rotating members, as well as the pitch, of the screw flights. This variation in the degree of diverting which may be realized is indicated diagrammatically in Fig. 5 by the change in direction represented by the arrows A and B. A slow speed will cause the material to run in a very close spiral path, such as indicated by arrow A, whereas a higher speed will produce a wider spiral, such as indicated at arrow B. This method of control makes it possible to discharge a product from the machine in either a uniformly coarse or uniformly fine condition, as desired. It will be apparent that the degree of intensity of deflection can be varied over a wide range as, for example, by using screw conveyor speeds from as slow as 30 R. P. M. up to and over 1000 R. P. M.

It is also pointed out that uniformity in the treatment of stock is further realized by preventing fibrous materials from adhering to the grooved surfaces of the top roll. I accomplish this result by having the flights of the screw constantly running in rolling contact with the grooved surfaces of the top roll so that there is no opportunity for fibers to collect. Moreover, such material as does collect on the top roll and is picked up by the flights of the screw becomes transferred on to the lower roll due to the rotative arrangement of the parts. Here it is pointed out that since the roll 42 is rotating in the same direction as the cylindrical casing, portions of fibrous material which come into contact or fall upon this lower roll are necessarily moved in a circular path which converges with and blends into the path of the main stream of material.

Attention is again directed to the rolls 14 and 42, as well as the cylindrical casing 10, shown in Fig. 1.. These members, in one preferred form, have been constructed with special means for preventing axial displacement of the cylindrical casing. It has been found that in supporting a heavy cylindrical casing in a suitable manner for rotation and while suspended on a top roll, there may arise a need for special retaining ring means at either end of the cylindrical casing in order to maintain it in a correct position. This is in practice found to appreciably increase the cost of manufacture, as well .as complicating the design and operation of the mechanism of the invention in some classes of the device. To obviate these difficulties I have devised a convex roll surface which may conveniently comprise two conical sections arranged with their bases against one another to produce a double frustrum structure. I have also constructed the cylindrical casing with a concave center section 72 which is complementary in contour with the convexity of the roll surface 70. By means of this arrangement it will readily be seen that the two members, when rotating, seek to center on one another and this tendency opposes forces acting to cause axial displacement so that occurrence of displacement is almost entirely prevented. With this structure I may form the screw 40 with flights which are complementary with the concavity of the cylindrical casing and I may also construct the lower roll 42 with a convex peripheral surface 42a also complementary with the concave cylindrical casing. It is pointed out that the invention is not necessarily limited to a double frustrum type of roll, and for some types of operations I may provide rolls 14a and 4211 which are true cylinders and which are adapted to be run in rolling contact with a true cylindrical casing surface. These roll members are illustrated in Fig. 4 of the drawings.

While I have shown a preferred embodiment of the invention it is intended that various changes and modifications may be resorted to in keeping with the scope of the invention as defined by the appended claims.

Having thus described my invention, what I desire to claim as new is:

1. In a machine for mechanically working fibrous paper making material, the combination of a revolving casing adapted to receive and move said fibrous paper making material in a circular stream, a roller located through the revolving casing in a position to engage against the paper making material, said roller being mounted for rotation about its longitudinal axis, and rotating screw conveyor means supported in close proximity to the inner peripheral surface of the casing along one side thereof, and supported in rolling contact with the said roller to remove fibrous material therefrom.

2. A structure according to claim 1, in which the surface of the said roller is formed with grooves and said screw is located in a position such that its flights are in rolling contact with the said grooved surfaces of said roller to remove material therefrom.

3. A structure according to claim 1, including a second roller located in rolling contact with the inner periphery of the revolving casing.

4. A structure according to claim 1, including a second roll located through the revolving casing, the first roll and said screw conveyor being located in cooperative rela tionship to the said two rolls with its flights in rolling contact with the surface of the first roll at points so chosen that the flights may scrape material from the said first roll and divert it on to the second roll.

5. In a machine for mechanically working fibrous paper making material, the combination of a revolving casing adapted to receive and move said fibrous paper making material in a circular stream, a roller located through the revolving casing in a position to engage against the paper making material, said roller being mounted for rotation about its longitudinal axis, and rotating screw conveyor means supported in close proximity to the inner peripheral surface of the casing along one side thereof and in contact with said roller, and a second roll located in rolling contact with the inner periphery of the revolving casing; said second roll having its longitudinal axis occurring below the longitudinal axis of both the revolving casing and the said rotating screw means.

6. A structure as defined in claim 5, including means for forcing said second roll against the revolving casing with varying degrees of pressure.

7. A structure according to claim 6, in which the said revolving casing is supported on the said first roll in rolling contact therewith, whereby the said means for conveying pressure operates to increase crushing force between said revolving casing and the said first roll.

8. A structure according to claim 7, in which the said rotating screw member is arranged in rolling contact with one of said rolls.

9. A structure according to claim 8, including means for rotating the revolving casing and the first and second rolls at varying speeds in a common direction, and means for rotating the screw member at varying speeds in an opposite direction.

10. A structure according to claim 9, in which the said screw member is formed with helical flights which extend in a direction opposed to the direction of rotation of the screw member.

11. In a machine for mechanically working fibrous paper making material, the combination with a roller, bearing means supporting said roller for rotation about a substantially horizontal axis, a revolving cylindrical casing surrounding the roller, inlet and outlet ports for the paper making material, said cylindrical casing being adapted to continuously move a fluid mixture of fibrous material in a circular stream which is centrifugally held against the inner peripheral surface of the casing and squeezed between the cylindrical casing and roller, means providing for relative movement between the roller and the cylinder to permit passage of relatively coarse pieces of paper making material therebetween, and rotating screw conveyor means arranged in rolling contact with the said roller and occurring in the path of movement of the circular stream for periodically diverting the said stream in directions axially of the casing and toward the outlet port, and a second roll located through the revolving casing in rolling contact therewith.

12. A structure as defined in claim 11, and said screw conveyor means having its axis of rotation so chosen as to locate the flights of said screw in rolling contact with the said first roll to remove fibrous material collected thereon.

13. A structure according to claim 12, in which the axis of the said second roll lies below the axes of both the said upper roll and the screw and in a vertical plane which passes through the axis of the said first roll, whereby material picked up by the screw from the first roll will be fed on to the second roll and thence in to the main stream.

14. In a machine for crushing fibrous paper making material, the combination of a roller, bearing means supporting said roller for rotation about a substantially horizontal axis, a revolving cylindrical casing, inlet and outlet ports for the paper making material communicating with the casing, said casing surrounding the roller and adapted to continuously move a fluid mixture of fibrous material in a circular stream which is centrifugally held against the inner peripheral surface of the casing and squeezed between the casing and roller, said cylindrical casing being movable away from and toward the roller to permit passage of relatively coarse pieces of paper making material therebetween, rotating conveyor means arranged in rolling contact with the said roller and disposed in the path of movement of the circular stream and cooperating with the casing to periodically divert the said stream axially of the casing and along distances which are proportionate to the speed of rotation of the conveyor means, the said cylindrical casing and roll being formed with complementary respective concave and convex midsections.

15. A structure according to claim 14, in which the said screw is formed with convex flights.

16. A structure according to claim 15', in which the said second roll is formed with a convex midsection.

References Cited in the file of this patent UNITED STATES PATENTS 2,674,162 Haug Apr. 6, 1954

Claims (1)

1. IN A MACHINE FOR MECHANICALLY WORKING FIBROUS PAPER MAKING MATERIAL, THE COMBINATION OF A REVOLVING CASING ADAPTED TO RECEIVE AND MOVE SAID FIBROUS PAPER MAKING MATERIAL IN A CIRCULAR STREAM, A ROLLER LOCATED THROUG THE REVOLVING CASING IN A POSITION TO ENGAGE AGAINST THE PAPER MAKING MATERIAL, SAID ROLLER BEING MOUNTED FOR ROTATION ABOUT ITS LONGITUDINAL AXIS, AND ROTATING SCREW CONVEYOR MEANS SUPPORTED IN CLOSE PROXIMITY TO THE INNER PERIPHERAL SURFACE OF THE CASING ALONG ONE SIDE THEREOF, AND SUPPORTED IN ROLLING CONTACT WITH THE SAID ROLLER TO REMOVE FIBROUS MATERIAL THEREFROM.

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