US2649717A - Rotary refiner - Google Patents

Description

Aug. 25, 1953 P. ARPIN, JR., ET AL ROTARY REFINER Filed Aug. 28, 1951 2 Sheets-Sheet 1 my WM H P H TM Aug. 25, 1953 E. P. ARPIN, JR, ETAL 2,649,717

' ROTARY REFINER Filed Aug. 28, 1951 2 Sheets-Sheet 2 IfiZ/EWZZITE Edmund 'Ar oizz Ji" Ra 511220220 P Five Patented Aug. 25, 1953 ROTARY REFINER Edmund P. Arpin, Jr., Neenah, Wis., and Raygo, 111.; said Frye assignor mond P. Frye, Chica to said Arpin Application August 28, 1951, Serial No. 244,006

Y 4'Claims.

This invention relates to improvements in rotary refining machineswhich are used to refine wet, fibrous material, such as pulp, paper stock and the like. More particularly the present invention has to do with improvements in rotor mountings and toimproved means for adjusting the rotors relative to the cooperating refining surfaces of the stationary abrasive shell within which the rotors are rotated.

In the operation of a rotary refiner according to our copending application for Patent Serial No. 37,338, filed July 7, 1948, now Patent No. 2,631,504, it was found that the construction was not entirely satisfactory under low consistency stock conditions. A construction has now been discovered and is herein set forth which is especially satisfactory under these conditions. The present application is directed to certain improvements over said application Serial No. 37,338.

It is therefore an important object of the present invention to provide a mounting for a refining element in a rotary refiner assembly which will operate very satisfactory under lowconsistency stock conditions.

It is another object of the invention to improve the contour of the refining members at their forward ends.

It is a further important object of this invention to provide a simpler and more economical construction which is also especially satisfactory under low. consistency stock conditions.

It is also an object of the invention to provide a novel self-adjusting wedging means for retaining the refiner elements in their backing plates.

Other and further important objects of this invention will be apparent from the disclosures in the, specification and the accompanying drawings.

On the drawings: a

Figure 1 is a longitudinal elevational view of a rotary vrefiner embodying the principles of our invention with parts broken away and in section, and with other parts in elevation. 7

Figure 2 is a fragmentary vertical sectional view taken substantially on the line II-l1 of Fig. l with parts in elevation.

Figure 3 is a fragmentary vertical sectional view taken substantially on line III-III of Fig. 2.

Figure 4 is a partial elevational view of a rear portion of one of the refiner members showing a modified form of wedge means for retaining the refiner elements in their'backing plates.

As shown on the drawings:

In Fig. 1, the reference numeral I indicates generally a rotary refiner embodying the principles of our invention, including a generally cylindrical shell or casing ll defining a support structure which is supported normally in horizontal condition upon suitable supports l2. The shell II is provided with end plates I3 and. M, the end plate l3 at the inlet end of the machine and having an inlet opening I5, and the plate M at the discharge end having a discharge opening l6. Each end plate is outwardly dished and provided with a central boss l8 defining a centralopening for receiving, in bearing relation, a hollow shaft 19. Said shaft I9 isadapted to be rotated centrally in the casing II by a grooved pulley 20. Disposed within the dished portion of the inlet end plate l3 and secured to the shaft is an impeller member 2| which receives the material as it enters the inlet opening l5 and directs it toward its periphery for subsequent passage between the workingsurfaces of the refining machine.

The shell II is provided internally with a liner 22, composed of a number of ring sections 23 which are formed of suitable abrasive material, such as stone, metal or a synthetic ceramic of an abrasive type.

As best seen in Fig. 2, a series of equally spaced helical grooves 24 extend longitudinally in the machineand form continuous passages along the inner surface of the ring sections 23.

The particular refining machine herein illustrated to disclose the novel rotor construction and mounting of the presentinvention includes rotor assemblies 25 pivotally mounted on a housing 26, in peripheral sets of four each, for rotation with the hollow shaft I9 to which a tubular central portion 33 is keyed. Each rotor assembly includes a refining element 21 secured in a backing plate 28 which has spaced upstanding ear ,por-

tions 3|, Fig. 3, which straddle flange parts 32 on the housing 26 and are pivotally mounted thereon by a pin 30. As the shaft [9 is rotated, the rotor moves outwardly by centrifugal force causing the refining element to coact with the abrasive surface of the liner ring 23 to refine the fibrous material as it is moved between the refining surfaces by the action of the impeller 2| and by the pressure head under which the material is delivered to. the inlet opening. Both the liner ring 23 and the rotor element .21 may be formed of stone,

metal or of a synthetic lever 35 pivotally mounted at centralhub portion 36, Figure 2 on the pin 30 which is journaled in the flanges 32 of the housing 26. One end 35a of the lever 35 is disposed in an aperture 39 of an arm 40 bolted to the radially inner surface of the backing plate 28. The other end 35b of the lever 35 is disposed in abutting contact with the end of a push rod 42 slidably mounted in aligned radial apertures in the hollow shaft l9 in the housing 26.

As a means for controlling the radially inward and outward movement of the push rods 42 there is provided a series of frusto-conical wedge members 43, Fig. 1, secured to telescoping rods 44, 45 and 46 extending longitudinally inside the shaft l9. It will be noted in Fig. 1 that two wedge members 43 are secured to each rod. The position of each of the rods 44, 45 and may be adjusted individually or they may be adjusted as a unit from the outside of the casing by means which we have described in detail in our above mentioned copending application, Serial No. 37,338, filed July 7, 1948.

The inner end of each push rod 42 Bin contact with the face of one of the wedge members 43 and, thus, the longitudinal positions in the shaft 19 of the members 42 determine the extent of outward pivoting of the rotor assemblies 25. A spring .8, Fig. 2, is disposed about the hub portion 38 of the rod 35 having end portion 49 resiliently urged into contact with the tubular portion 33 of the housing 26 and a roller equipped end portion 59 in contact with the face of the backing plate 28. This spring 48 prevents the rotor stone assembly 25 from dropping away from the ring 23 when the machine is shut down.

Further details of construction and operating of a refining machine to-which our novel rotor construction and actuating means may be applied, may be had by reference to U. S. Patent No. 2,475,869 to Edmund P. Arpin, Jr., on application Serial No. 640,734 filed January 12, 1946.

Referring to Fig. 2, the backing plate 28 comprises a substantially fiat central portion 52 with an overhanging ledge 53 which extends across the leading end of the plate forming a heel against which the corresponding portion of the stone 2? is pressed when the rotor is assembled therein. 7 a

At both sides of the backing plate, a wall portion 55, Fig. 1, extends away from the flat central portion 52 to provide a recessed chamber which is adapted to receive, in guiding relation,

a strip 57 formed on the stone 21 to fit in the chamber.

As shown in Fig. 2, a metal pressure pad 59'is disposed across the trailing edge of the rotor stone with a pad of cushioning material between the surfaces of the pad 59 and the stone. This cushioning pad which may be made of a material such as rubber, soft metal alloy or plastiaprotects the stone surface under compression against metal surfaces. In this connection, a cushioning pad may be disposed between'the rotor stone strip and the backing plate 52 and also between the metal housing I i and the various ring sections 23 which form the abrasive lining.

A series of wedges 62 are disposedbetweena marginal flange E3 at the trailing edge of the backing plate 28 and the pressure pads 59.

fining element 21".

4 the rotor stone and firmly urge it into place in the backing plate 28.

It is therefore seen that there is provided a wedge means for adjustably securing a rotor stone in a backing plate. Since this wedge means is disposed at the outer periphery of the rotor each refining element may be removed from or inserted into the backing plate without disturbing the adjacent rotor assemblies in the refining machine. Further, the pressure pad 59 which extends across the width of the refining element provides means for uniformly distributing the pressure exerted by the clamping means on the refining element.

The present invention thus provides a single pivot pin 30 for both the backing plates 28 and thelevers 35 for simplicity and economy. In our copending application Serial No. 37,338 above mentioned, a line from the longitudinal axis of the machine through the center of the pins pivotally mounting the leading portions of the refiner members intersected the leading portions of the refiner members or rotor elements. In the present invention such a line through the pivot pins 36 leads the leading portions of the refiner members by a substantial amount. That is, considering a certain transverse plane including a cross section of a pivot pin 30, and referring to Figure 2, it will'be observed that a line from the center-of a cross section of shaft 43 in said transverse plane and extending radially outwardly through the center of said cross section of pin J8 is circumferentially spaced ahead of the leading portionof the rotor element 28 by a substantial amount. This condition will be described as one wherein the pivot pin radius arm leads the leading portions of the rotor elements by a substantial amount and is spaced forwardly ahead of the leading edge. It will further be observed that the ear portions 3! are of substantially greater length. It is believed that these conditions of a leading pivot pin radius "arm and the greater length of the ear portions rock on the contacted surface ill of the backing plate 28 and thus automatically adjust for best contact through a pressure pad 59 with the re- Primed numerals refer to parts similar to those shown in Figure 2. Retainin-g pressure exerted on the refining element is thus distributed over a greater area.

It will be understood that various details of construction may be varied through a widerange without departing from the principles 5f the present invention, and it is, therefore, not the purpose to limit the patent granted thereon otherwise than necessitated by the scope of the euately spaced positions, levers each .pivotally vmounted intermediate the ends thereof, on one of said pins and having free end portions,- a rod associated with one end of each lever and extending radially through said hollow shaft, an arm portion projecting from the trailing end of each of said rotor elements and having an aperture for receiving the other end of each of said levers, and means in said hollow shaft associated with the radially inward end of each rod for controlling the amount of clearance between said rotor and said cylindrical shell; the improve-- ments which comprises pivotally mounting the leading portion of each rotor element on the same pin which pivotally mounts the lever associated with the trailing portion of the rotor element next ahead.

2. In a rotary refiner for wet fibrous material of the type including a stationary shell having a cylindrical abrasive liner, a drive shaft, centrifugally acting rotor elements movable against said abrasive liner, members secured to said shaft, levers pivotally mounted intermediate their ends on said members and having free end portions, an arm portion projecting from each of said elements having means for receiving one end of each of said levers, and means operatively associated with the other end of each of said levers for efiecting pivotal movement of the lever to control the amount of clearance between said rotor and said cylindrical shell; the improvement which comprises a single pin pivotally connecting the leading portion of each of said rotor elements to one of said members, each pin mounting the leading portion of one rotor element and the lever associated with the trailing portion of the next succeeding rotor element.

3. In a rotary refiner for wet fibrous material of the type including a stationary shell having a cylindrical abrasive liner, a drive shaft, centrifugally acting rotor elements movable against said abrasive liner, members secured to said shaft, levers pivotally mounted intermediate their ends on said members and having free end portions, an arm portion projecting from each of said elements and having means for receiving one end of each of said levers, and means operatively associated with the other end of each lever for efi'ecting pivotal movement of the lever to control the amount of clearance between said rotor and said cylindrical shell; the improvement which comprises an elongated lever arm functionally integral with the leading portion of each of said rotor elements and extending forwardly therefrom, a single pin pivotally mounting the forward end of said lever arm to one of said members, said lever am being so constructed and arranged that a radius line in a transverse plane of the refiner and extending from the central axis of the drive shaft and through the center of said pin is substantially spaced ahead of the leading portion of said rotor element carried by said pin in the direction of rotation of said rotor element.

4. In a rotary refiner for wet fibrous material, a rotor assembly comprising a backing plate, a stone refining element positioned in said backing plate, a pressure pad extending across one end of said refining element and adjustable wedge member abutting said pressure pad to urge said element into said backing plate, said pad being effective to evenly distribute the pressure of said wedge member across the end of said element, said wedge members having convexly arcuate outer backing plate-engaging faces for rocking self-adjustment for further even distribution of pressure across the end of said element.

EDMUND P. ARPIN, JR. RAYMOND P. FRYE.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,331,969 Tomlimson Feb. 24, 1920 1,689,190 Arpin Oct. 30, 1928 1,714,752 Arpin May 28, 1929 1,854,652 Kirchner Apr. 19, 1932 1,908,842 Hermann May 16, 1933 2,086,383 Gruender July 6, 1937 2,475,869 Arpin July 12, 1949 2,566,869 Arpin 1.. Sept. 4, 1951

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