US2811904A

US2811904A - Fiber stock refining apparatus

Info

Publication number: US2811904A
Application number: US523180A
Authority: US
Inventors: Jr Orange S Herrington
Original assignee: Masonite Corp
Current assignee: Masonite Corp
Priority date: 1955-07-20
Filing date: 1955-07-20
Publication date: 1957-11-05
Anticipated expiration: 1974-11-05

Description

Nov. 5, 1957 O. S. HERRINGTON, JR

FIBER STOCK REFINING APPARATUS Filed July 20, 1955 ATTORN EY United States Patent r 2,811,904 FIBER STOCK REFINING APPARATUS Orange S. Herrington, Jr., Ellisville, Miss., assignor; to Masonite Corporation, Laurel, Miss., a corporation of Delaware Application July 20, 1955, Serial No. 523,180

4 Claims. (Cl. 92-27) This invention relates to fiber stock refining apparatus, and relates more particularly to refining engines of the Jordan type.

The present invention constitutes an improvement over the refining apparatus disclosed in Patent No. 1,775,743 to J. A. Wiener, issued September 16, 1930. In both inventions, the fiber stock is fed into the larger end of a refiner similar to the usual Jordan in its construction but, in the present invention, the impeller blades are improved over those of the above referred to patent.

. It is therefore a primary object of the present invention to provide a refining apparatus of the Jordan type, wherein improved impeller means are provided for greatly increasing the efficiency and life of the refining apparatus and, also, improving the quality of the refined stock.

Other important objects of the invention will be apparent from the following detailed description thereof and from the accompanying drawings in which:

Fig. 1 is a sectional side elevation through the apparatus,

Fig. 2 is an enlarged sectional view taken on line 22 of Fig. 1, and

Fig. 3 is an enlarged sectional side view of the impeller blades of the apparatus.

In the drawings, the numeral indicates a base adapted to support the fiber refining apparatus 12. Said refining apparatus 12 comprises a casing 14 made up of an intermediate frusto-conical shell 16 having secured thereto at its smaller end a passaged section 18 forming a discharge port 20 communicating with the bore of the shell 16 by means of an opening 22. A passaged section 24 is joined to the larger end of the shell 16 through an annular spacing ring 26. Said section 24 is formed with an enlarged intake port 28 opening into the hollow interior 30 of said section. The stock admitted into the intake port 28 passes from the interior 30 of said section 24 through a central opening 32 into the space 34 formed by the annular spacing ring 26.

A plug 36, substantially frusto-conical in shape, is mounted axially within the shell 16 upon shaft 38 adapted to be driven through a coupling 40 and supported in hearing housings 41 and 42 from the base 10 in customary manner. Conventional means are provided for longitudinal adjustment of the plug Within the frusto-conical shell as indicated generally at 43.

At the larger end of the plug 36 there is formed a reduced portion 44 having a reverse taper 45 to that of the major part of the plug. There is thus provided a wedge shaped space 46 between the inner surface of the shell 16 and the reduced portion 44 of the plug for facilitating the admission of stock between the refining surfaces of the plug and shell respectively.

The refining elements comprise

knives

48 and 50 set along the bore of the shell 16 and in the plug 36 respectively in the usual manner. It should be noted, however, that the knives 50 positioned on the plug 36 extend along the surface of the reduced portion 44 as at 52 and are co-extensive with the length of said plug. By virtue of 2,811,904 Patented Nov. 5, 1957 ice this construction, the portions 52 of the knives 50 act much in the same manner as the runner blades of a pump to force the stock between the refining elements.

An impeller 54, comprised of a base plate 55 and radially extending straight blades 56 secured to the larger end of the plug 36 by the screws 57, serves as the main impelling force for causing the stock to flow through the refining engine in a direction reverse to that normally taken by the stock in the usual Jordan engine. The blades 56 of the impeller 54 are substantially the width of the annular chamber 46, leaving but a small clearance between the edge of the central opening 32 and the outer edge of the blades 56.

.The novel improvement of the present invention comprises the provision of a recessed portion 58 in each of said impeller blades 56 at the edge thereof which is secured to the plug 36. The recessed portion 58 creates a turbulence in the stock which is outstandingly beneficial in increasing the useful life of the plug 36 and, as well, results in refined stock of improved quality.

As stated hereinbefore, the impeller 54 serves as the main impelling force for causing the stock to fiow through the refining engine. In the prior art refiners, the solid design of the impeller blades caused a major proportion of stock to be forced between a relatively few of the knives on the plug located most closely adjacent to the impeller blades. As a consequence, the normally sharp edges of the knives which were most heavily loaded became dull and rounded in a short time. Stock passing through the refiner was thus characterized by a progressively greater lack of refining. Adjustment of the plug in a horizontal direction to smaller clearance was continuously necessary until the point was reached where improvement was possible only by dressing the dulled knives of the plug. This undesirable condition existed over a period of several years.

It was recently discovered, quite unexpectedly, that the provision of a recess in each of the impeller blades overcomes the undesirable characteristics of the prior art refining engines. As the plug is rotated during use, the recessed portion 58 of each impeller blade 56 allows a portion of the stock to escape from being immediately forced through the refiner. The turbulence thus created results in the stock being evenly disturbed between all of the knives of the machine. Due to this uniform stock distribution, the brushing action of the fibers against each other is greatly enhanced as is the shearing action of the knives.

An outstanding advantage derived from the novel improved impeller blades of the invention resides in the greatly increased useful life of the plug 36. It has been found that refining engines constructed according to the invention may be used continuously for a period of time many times greater, before any reconditioning is necessary, than is possible with the prior art refiners.

While the size of the recessed portion 58 is not entirely critical, obviously it must be large enough to create the necessary turbulence in stock flow. On the other hand, the recessed portion must not be so large as to either seriously decrease the impelling action of the blades 56 or to weaken the blades to the extent where breakage thereof will occur. Inasmuch as the size of any particular refining engine is dependent on the capacity desired thereof, it is impossible to attribute any numerical criterion as to the size of the impeller blade recess. However, it has been found that a recess size of the order of magnitude of about 10-20% of the impeller blade face area provides exceptionally good results, with the preferred size being about 15%. The recessed portion 58 has been shown in the drawings as being rectangular in shape although it may obviously be rounded or curved, or of any shape which functions satisfactorily.

Asmany apparently widely different embodiments of the invention may be made without departing from the spirit thereof, it is to be understood that the scope of the invention is not to be limited to specific embodiments thereof except as defined in the appendedclaims.

' I claim:

1. A fiber stock refining apparatus comprising a shell having a frusto-conical shaped bore, a frusto-conical shaped plug adjustably mounted in'said bore and having a reversely tapered portion at its larger end, straight impeller blades secured to the larger end of said plug and extending radially substantially to the periphery thereof, each of said impeller blades being recessed at the outermost part of the blade edge, and means for introducing fiber stock at the larger end of said shell for passage through said bore to the smaller end.

2. A fiber stock refining apparatus comprising a shell .having a frusto-conical shaped bore, a frusto-conical 'shaped plug adjustably mounted in said bore and having a reversely tapered portion at its larger end, straight impeller blades secured to the larger end of said plug and extending radially substantially to the periphery thereof, each of said impeller blades being recessed atthe outermost part of the blade edge which is secured to the plug, and means for introducing fiber stock at the larger end of said shell for passage through said bore to the smaller end.

3. A fiber stock refining apparatus comprising a shell having a frusto-conical shaped bore, a frusto-conical shaped plug adjustably mounted in said bore and having a reversely tapered portion at its larger end, straight impeller blades secured to the larger end of said plug and extending radially substantially to the periphery thereof, each of said impeller blades recessed at the outermost part of the blade edge which is secured to the plug, the area of said recess comprising about 10-20% of the blade face area, and means for introducing fiber stock at the larger end of said shell for passage through said bore to the smaller end.

4. In a fiber stock refining apparatus comprising a shell having a frusto-conical shaped bore, a frusto-conical shaped plug adjustably mounted in said bore and having a reversely tapered portion at its larger end, straight impeller blades secured to the larger end of said plug and extending radially substantially to the periphery thereof, and having means for introducing'fiber stock at the larger end of said shell for passage through said bore to the smaller end, the improvement which consists in the provision of a recess at the outermost part of each blade edge which is secured to the plug, the area of said recess comprising about 10-20% of the blade face area.

References Cited in the fileof this patent UNITED STATES PATENTS 581,605 Mills Apr. 27, 1897 1,467,207 Strattman Sept. 24, 1923 1,730,908 Wiener Oct. 8, 1929 1,775,743 Wiener Sept. 16, 1930 1,971,335 Benner et a1 Aug. 28, 1934 2,294,060 Wiener Aug. 25, 1942 2,694,344 White Nov. 16, 1954