US 3349462 A
Description (OCR text may contain errors)
| H. MOTT 3,349,462
AIR ROLLER Oct. 31, 1.967
Filed June 14, 1966 INVENTOR: LAMBERT H. MOTT ATTOR N EY United States Patent ()fiiice 3,349,462 Patented Oct. 31, 1967 3,349,462 AIR ROLLER Lambert H. Mott, Farmington, Conn. (272 Huyshope Ave., Hartford, Conn. 06114) Filed June 14, 1966, Ser. No. 557,585 2 Claims. (Cl. 29116) This invention relates in general to rollers used in textile machinery known as separator rolls over which filaments pass; and, more particularly, to air supported rollers of this type.
Rollers of many types are used in textile machines to guide or pass filaments thereover. If conventional ball or roller bearing supported rollers are used, they require lubrication which may fly off or drip to stain textile products being produced. Also, conventional bearings wear out and must be replaced after a period of operation because, although the loads are light, high speed rotation is involved. Air supported or air lubricated rollers have been used, but these rollers have required such large volumes of air and so many rollers are used in textile machines that maintaining a sufficient supply of pressurized air presented difficulties and was not economically feasible.
It is, therefore, a main object of this invention to provide an air roller for use on a textile machine which has a minimum air supply requirement.
Another object of this invention is to provide an air roller for a textile machine which has the lowest possible inertia.
A further object of this invention is to provide an air roller for a textile machine which is less expensive to manufacture.
Many other objects, advantages, and features of invention reside in the particular construction, combination, and arrangement of parts involved in the embodiment of -my invention and its practice as will be understood from the following description and accompanying drawing wherein:
FIGURE 1 is a longitudinal section through an air roller according to my invention;
FIGURE 2 is an end view of the air roller of FIGURE 1; and
FIGURE 3 is a side view of another air roller which may be fabricated according to this invention.
Referring to the drawing in detail, an air roller according to my invention has a stem which is machined to leave a larger diameter collar 11 at one end of a smaller diameter shaft 12. A threaded extension 14 is used to mount stem 10 and supply pressurized air to the roller. An air passage 15 is bored'in extension 14 to meet the transverse aperture 16 drilled through shaft 12.
A porous metal cylinder 20 is formed to contain a central passage 21 of substantially the same diameter as collar 11. Passage 21 extends substantially the length of cylinder 20 to terminate in a smaller portion 22 which is of substantially the same diameter as shaft 12. Thus stem 10 may be pressed into cylinder 20 leaving a central compartment 24 which is supplied with compressed air through passage 15.
Cylinder 20 is formed of porous metal, preferably porous stainless steel to minimize corrosion. It should be formed from a metal powder with a grain size less than .001" compacted to have a porosity of less than 20 percent. This results in a cylinder 20 of low permeability which restricts the flow of air from compartment 24 to the outer surface 25 of cylinder 20 and to its ends 26 and 27.
A tubular shell 30 has an end plate 31 crimped in one end. Plate 31 contains an air escape aperture 32. At least one flange 33 is formed on shell 30 to guide filaments passing thereover. A second end plate 34 is fixed in shell 30 by means of a retaining ring 35 which expands into an inner groove 36. End plate 34 contains a central opening 37 which extends with a slight clearance 38 about collar 11 to allow the escape of air. Thus it may be seen that air introduced into passage 15 will escape through cylinder 20 to float and longitudinally position shell 30 so that it may rotate freely.
To operate satisfactorily with a minimum flow of air, shell 30 should have a radial clearance of less than .001" from the outer surface 25 of cylinder 20. However, the end plates 31 and 34 should be, between them, a total distance of more than .005" from the end surfaces 26 and 27 of cylinder 20. If the sum of the clearances between the end plates 31 and 34 and the surfaces 26 and 27 is less than .005, an undesirable longitudinal vibration will be set up in the shell 30 during operation of the air roller.
The shell 30 may rotate at 15,000 rpm. so that inertia on rapid starting and stopping is an important factor. Thus shell 30 and end plates 31 and 34 are made as thin and light as possible to reduce inertia and prevent filament breakage and distortion.
FIGURE 3 shows a roller 40 similar to that described which has two guide flanges 41 and 42 formed on it. These rollers, as shown in FIGURES 1 and 3, are known as separator rollers in the textile trade and are from .75" to 2" in diameter and from 1" to 8" in length. The air roller of this invention is inexpensive to manufacture and it is economical in its use of air. As one example, an air roller built according to this invention was .825" in diameter with a porous cylinder 20 .75" in diameter. This roller was 2" long. The roller required air at a pressure of 10 p.s.i. to rotate and, at this pressure, used cc. of air per minute. At 15 p.s.i., it used cc. of air per minute; at 20 p.s.i., it used cc. of air; at 25 p.s.i., it used 220 cc. of air; at 30 p.s.i., it used 250 cc. of air. Thus it may be seen that the air roller of this invention operates at a wide range of pressures with a minimum air consumption.
While this invention has been shown and described in the best form known, it will be understood that this is purely exemplary and that modifications may be made without departing from the spirit and scope of the invention except as it may be more limited in the appended claims wherein I claim:
1. An air roller for textile machines for passing filaments thereover, said air roller comprising, in combination, a stem having a shaft portion, a cylinder with flat ends and a porous metal disposed about said shaft portion of said stem forming a compartment between said shaft portion and said cylinder extending substantially the length of said cylinder, said stern containing an air passage communicating with said compartment, said cylinder being formed from a metal powder with a grain size less than .001" compacted to have a porosity less than 20 percent, and a thin shell having at least one guide flange and extending about said cylinder with a radial clearance less than .001", said shell having a first end plate with a central air escape aperture and a second end plate containing an aperture through which said stem extends with a clearance to allow the escape of air, the sum of the distances between said end plates and the ends of said cylinder being greater than .005".
2. The combination according to claim 1 with the addition of a collar at one end of said shaft portion of said stem, said cylinder extending about said shaft portion at the end opposite said collar, said cylinder being ameter as said collar forming said compartment which is closed at one end by said collar.
References Cited UNITED STATES PATENTS 2,610,096 9/1952 Mallory 308-9 2,645,534 7/1953 Becker 3089 2,696,410 12/1954 Topanelian 308--9 3,156,399 11/1964 Wadey 3089 XR 3,221,389 12/1965 Cowell 29-116 FOREIGN PATENTS 724,603 2/ 1955 Great Britain.
bored out substantially its entire length the same di- 15 BILLY I. WILHITE, m y Examiner-