US 3216349 A
Description (OCR text may contain errors)
Nov. 9 1965 R. KRAFT 3,216,349
APPARATUS FOR TREATING SHEET MATERIAL Filed Feb. 21, 1963 la'llmllln /n venfor RUPERT KRAFT A 170/0 6 yj United States Patent 3,216,349 APPARATUS FOR TREATING SHEET MATERIAL Rupert Kraft, Klagenfurt, Carinthia, Austria, assignor to Maschinenfabrik Johannes Zimmer, Klagenfurt, Carinthia, Austria Filed Feb. 21, 1963, Ser. No. 260,140 Claims. (Cl. 101123) This invention relates to an apparatus for treating sheet material, particularly for printing textile fabrics and the like and comprises a roller which is urged by magnetic forces against the material to be treated and which is moved relative to same in rolling contact therewith.
In a known apparatus of this kind, the roller for treating a web of material is forced against the latter by a magnet which is disposed on the opposite side of the web.
When it is desired to treat a material of greater thickness, e.g., to print a carpet web or the like, the distance between the surface of the magnet and the magnetically attracted doctor roller is so large that the magnetic flux densities normally available will not result in a sufiiciently high contact pressure.
To eliminate this disadvantage it is proposed according to the invention to provide the roller with at least two axially spaced portions which constitute magnetic poles and to provide magnetic means having magnetic poles each of which is closely spaced over a like magnetic pole of said roll.
The magnets having magnetic poles closely spaced over like magnetic poles of the doctor roller give rise to a repelling force urging the cylinder against the material to be treated.
In order to ensure that the magnetic poles of the doctor roller will be constantly maintained exactly under the magnetic poles of the magnets, guide means may be provided at the ends of the roller or, where the roller is entirely freely arranged, the magnetic poles of the repelling magnets disposed over the roller may be shaped to surround a portion of the periphery of the roller. Owing to this design of the magnetic poles of the repelling magnets, the doctor roller is surrounded by repelling forces so that its longitudinal axis will always lie exactly under the repelling magnets.
A doctor roller having magnetic magnetic poles may be provided by a provision of magnetic rollers known I per se.
It has been found particularly suitable, however, to use a so-called magnetic rubber composition. In this case the particles of permanently magnetizable material embedded in rubber or another elastomer are given a permanent magnetization and annular magnetic poles are obtained on the surface of the roller.
The sheet material to be treated may be moved below the doctor roller or the latter may be moved over the sheet material held in position. In this case the repelling magnets are moved in the desired direction of movement of the doctor roller and entrain the same while applying repelling forces thereon. Hence, the doctor roller is forced against the material to be treated and rolls along the same. The use of electromagnets enables an adjustment of the contact pressure of the roller.
A plurality of embodiments of the invention are shown by way of example on the drawing.
FIGS. 1 and 2, respectively, are longitudinal sectional views showing two embodiments of the invention.
FIG. 3 illustrates a modification of FIG. 2 in a fragmentary sectional perspective view taken on a line corresponding to line AA of FIG. 2.
FIG. 4 is a fragmentary transverse sectional view illustrating another modification.
In all figures of the drawing, like reference characters indicate like parts.
The sheet material 1 lying on a base 21 is treated by a roller, which is indicated at 2 in FIG. 1 and may consist of a doctor roller, which causes the material 1 to be printed under control of a stencil 11.
In the embodiment shown in FIG. 1 the roller 2 consists of a bar magnet having opposite end portions, which form a magnetic north pole N and a magnetic south pole S, respectively. A north pole N of a repelling magnet 3 is closely spaced over the north pole N of the roller 2 and a south pole S of a repelling magnet 4 is closely spaced over the south pole S of the roller 2. The closely spaced like poles exert a repelling force on the roller 2 so that the latter is forced against the stencil 11. To prevent the roller 2 from yielding laterally under the repelling force, the roller 2 is formed at opposite ends with axial bearings 22 and two angular guide members 6 are provided on opposite ends of the roller 2.- Each of the guide members 6 has a horizontal portion extending into one of the bearings 22 and a vertical portion. Each of the repelling magnets 3 and 4 carries a retaining member ,5 formed with a hole 23, through which the vertical portion of one of the guide members 6 slidably extends. This arrangement enables a bodily movement of the roller 2 relative to the magnets 3, 4 only in the direction of the repelling force. The magnets 3 and 4 may be secured to a frame or housing 10. For a treatment of the web of material 1, the latter may be moved under the roller 2 or the roller 2 may be moved together with the magnets 3 and 4 over the web of material 1.
FIG. 2 shows an embodiment in which the roller 2" rolls on the material 1 without being supported in bearings. The roller 2 has axially spaced magnetic north poles 24 and magnetic south poles 25 in alternation. The magnetic members, which surround the core of the roller 2 and are axially spaced apart by non-magnetic portions. The peripheral surface of the roller 2 is formed by a rubber covering 26.
v The repelling magnets 3 and 4 are provided in a number corresponding to the magnetic north and south poles, respectively, of the roller 2 and are carried by a frame 10', which is guided at both ends in a direction transverse to the axis of the roller 2' by an angular guide surface 31 of a rigid guide structure 32 secured to the base 21. This guide structure 32 is shown only at one end of the frame 10' but may obviously be duplicated at the other end.
The repelling magnets 3 and 4 have pole pieces 7 providing magnetic poles closely spaced over like magnetic poles of the roller 2'. The pole pieces 7 form extensions which surround a portion of the peripheral surface of the roller 2' so that the roller 2 is forced against the base 21 without being able to yield laterally. The roller 2' will follow the movement of the magnets 3 and 4.
FIG. 3 shows a modification of the embodiment of FIG. 2. The roller 2" has a steel core 33 and a covering of magnetic rubber 27, which is magnetized in axially spaced zones to provide north poles 28 and south poles 29 in alternation. In other respects, the arrangement is similar to that of FIG. 2.
FIG. 4 shows a further modification of the embodiments illustratedin FIGS. 2 and 3. According to this modification, the repelling magnets consist of electromagnets comprising eaoh a magnet core 8 which is surrounded by the ma-gnetizing coil 9 and is formed or provided at one end with a pole piece 7' partly surrounding the roller 34. A rheostat 30 in series with the magnetizing coil 9 enables an adjustment of the repelling force exerted by the electromagnet 8, 9 on the roller 34. The roller 34 may be formed like any of the rollers 2, 2' or 2" of FIGS. 1 to 3.
The thickness of the rollers 2, 2', 2" or 34 and the form of the magnetic pole piece 7 may be determined in view of the material to be treated and the desired treatment thereof. Various modifications of the embodiments shown are within the scope of the invention. For instance, the retaining means formed in the embodiment of FIG. 1 by the guide means 5, 6 and in the embodiments of FIGS. 2 to 4 by the pole pieces 7 or 7' could be interchanged. Guide structure such as shown at 31, 32 in FIG. 2 could be provided in the embodiment of FIG. 1. The roller in the embodiment of FIG. 1 could be replaced by the roller 2' or 2" of FIGS. 2 and 3. The magnets 3 and 4 in FIG. 1 could consist of electromagnets such as shown at 8, 9 in FIG. 4. Means other than the rheostat 30 in FIG. 4 may be provided to vary the energization of the electro-magnets 8, 9. The provision of magnetic north and south poles in alternation is desirable in many cases but may be replaced by any other suitable arrangement of magnetic poles spaced in the axial direction of the roller provided that magnetic poles of the repelling magnet means are closely spaced over like magnetic poles of the roller.
What is claimed is:
1. Apparatus for treating sheet material, comprising a roller adapted to have rolling contact with the sheet material, means for mounting the roller for free vertical movement, means urging the roller downwardly to have pressure contact with the material, said last-named means comprising repelling magnets, said roller comprising an elongated core and a plurality of magnetic members surrounding said core, said magnetic members being axially spaced apart by non-magnetic members, said magnetic members providing spaced poles on the roller, said spaced poles on said roller being opposed by closely positioned poles of like polarity in repelling magnets thereabove said roller being held in spaced relation and out of substantial friction contact with said magnets by magnetic repulsion, and means for restricting the horizontal lateral and longitudinal movement of said roller with respect to the mag nets so as to keep the respective like opposed poles in substantial vertical alignment.
2. The invention as recited in claim 1, wherein said repelling magnets are laterally spaced, vertically extending magnets corresponding in number to the number of the magnetic members of the roller and respectively vertically aligned therewith.
3. The invention as defined in claim 2, wherein the lower end of said vertically extending magnets has horizontally aligned curved recesses receiving said roller.
4. Apparatus for treating sheet material which comprises a roller mounted to move relative to said material in rolling contact therewith and having at least two axially spaced pole portions constituting magnetic pole-s, said apparatus further comprising repelling magnetic means having repelling pole portions forming magnetic .poles, each of which is closely spaced over a magnetic pole of like polarity of said roller, and said roller having free vertical movement with respect to the magnetic poles of said magnetic means and held by said repelling force substantially out of friction contact therewith, said roller having a peripheral surface formed by magnetic rubber, which has axially spaced annular permanent magnetic pofitions forming said magnetic pole portions of said ro er.
5. Apparatus for treating sheet material which comprises a roller mounted to move relative to said material in rolling contact therewith and having at least two axially spaced pole portion-s constituting magnetic poles, said apparatus further comprising repelling magnetic means having repelling .pole portions forming magnetic poles, each of which is closely spaced over a magnetic pole of like polarity of said roller, and said roller having free vertical movement with respect to the magnetic poles of said magnetic means and held by said repelling force substantially out of friction contact therewith, a frame structure carrying said repelling magnetic means, a support having a top surface disposed under said roller and adapted to receive said material to be treated, and a guide structure fixed to said support and in guiding engagement with said frame structure to guide the same relative to said support in a horizontal direction normal to the axis of said roller.
References Cited by the Examiner UNITED STATES PATENTS 408,465 8/89 Dewey 308-10 1,470,962 10/23 Dibble et al 101-123 X 2,959,832 11/60 Baermann 317-158 X 2,965,020 12/60 Zimmer 101-123 3,089,175 5/63 Hinder 15-250.36
FOREIGN PATENTS 878,094 9/61 Great Britain.
OTHER REFERENCES Gardner: What You Can Do with Flexible Magnets, Product Engineering, Jan. 9, 1961, pp. -68, 317-158 Pub.
ROBERT E. PULFREY, Primary Examiner.
EUGENE R. CAPOZIO, Examiner.
UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,216,349 November 9, 1965 Rupert Kraft pears in the above numbered pat- It is hereby certified that error ap Patent should read as ent requiring correction and that the said Letters corrected below.
In the heading to the printed specification, after line 6, insert the following:
Claims priority, application Austria, Feb. 26, 1962,
Signed and sealed this 3rd day of January 1967.
ERNEST W. SWIDER Attesting Officer EDWARD J. BRENNER Commissioner of Patents