DE1916145A1 - Magnetic disk cylinder - Google Patents

Description

Magnetic disk cylinder The usual way nowadays, magnetic disk cylinder consists in the use of soft iron washers as pole pieces, those with permanent magnet washers on a cylindrical steel body with suitable Alternate bearing journals for bearing and drive devices. The magnets will assembled so that like poles abut against each pole piece. The strongest Magnets nowadays are made of ceramic material, which is due to difficult to work with due to its extreme hardness and brittleness. It is therefore It is common practice to bypass the machining process and to use epoxy resin to fill the pores use. The magnetic washers can consist of one piece or in Porm of segments, while the steel washers are usually in one piece Construction are made. If the steel body is made of an alloy, capable of magnetic attraction so this must against the Washers, usually by means of bronze bushings between the steel body and the washers to be isolated. In order to achieve maximum efficiency, it is important that there is contact between magnets and pole pieces. The variation and the thickness the magnet makes this impossible except for a few places. The assembly all of these parts with careful application and curing of the epoxy resin is a time consuming, expensive and ineffective process. Because the roller body much smaller in diameter than the outside diameter of the assembled and must be finished roll, one has to deal with the loss of rigidity in the Satisfy the roller, which in turn easily leads to unwanted distraction as well Jumping while the printer can result.

Because the steel support material of the sheet is very thin and of the order of magnitude From 0.178 mm to about 0.28 mm (0.007 "- 0.011"), pole pieces and magnets must be used also be very thin to produce maximum sustaining flow0 any loss of flow is likely to have insufficient holding force at the leading and trailing edges of the Cause pressure plate, whereby these edges are bent outwards.

According to the invention, a novel construction is now to be proposed with pole pieces and magnets in elements with, for example, a U-profile be prefabricated, with these elements in the slots of the plate cylinder body fit and held down by screws, being a turning and grinding process with the roller. The profile itself can be made of brass, aluminum or non-magnetic Stainless material are made to adequately prevent the flow against the steel body shield or isolate to maximize flux from pole piece to pole w ck to be reached through the thin sheet metal support. This construction makes the important thing The aim is to have magnets and pole pieces at right angles to the axis of the PrEo «file in the Positioned for maximum efficiency.

An example embodiment of the invention will now be based on of the accompanying drawings are explained in more detail, in which Figure 1 is a view partly in section through a plate cylinder according to the invention; Figure 2 is an enlarged section taken along line 2-2 in Figure 1; Figure 3 is a partial plan view in the direction of arrows 3 - 3 in Figure 2; and Figure 4 is a partial section along the line 4 - 4 in FIG. 3.

According to the illustration and according to FIGS. 1 and 2, the reference symbol denotes 10 essentially a plate cylinder equipped with the usual bearing pin 11 iet. The surface of the cylinder is axially elongated with slots, for example at 12, 13 eXc. (see Figure 2) interrupted to accommodate magnetic insert devices, which are generally designated 14 and 15. The invention is only concerned with that with 14 and is shown in more detail in FIGS. In other words, the difference between the magnetic hold-down means that at 14 and 15 are shown as being in the direction of polarity of the magnetic elements must be specified horizontally. According to the representation shown in Figures 3 and 4 shows that the permanent magnets with their longer dimensions perpendicular to the axial Length of the cylinder so that a flow is shown as at F in Figure 4, - which runs in the longitudinal direction or axially aüm cylinder. The type the hold-down device shown at 15 is to be used as between 4Rch Consider the hold-down beam, its flow is in one direction around the perimeter of the Cylinder 10 around.

The element 14 initially comprises a substantially U-shaped profile Element 16, which, as stated above, made of flow-insulating material, for example Bronze, aluminum, non-magnetic stainless steel etc. is constructed. at the use of the expression "U-profile-shaped" is not intended to limit the purchase price be taken, as trapezoidal formations, dovetail profile and the like. can also be used to advantage. First, the U-profile 16 becomes independent produced by the roller 10. The roller 10 is only with a suitable slot or slots as shown at 12, fitted to the finished U-profile element to record. The U-profile element comprises a plurality of permanent magnets, as in 17 and 18 (Figure 4) is shown. These magnets are built in, being similar Poles are arranged adjacent to each other.

A pole piece 16 is inserted between the same poles and the The arrangement of the plurality of pole pieces and magnets is securely connected by gluing them together by means of a Wpoxy resin, as shown at 20. At suitable points along the length of the U-profile 16, the finished element is drilled, as shown at 21, and receives a securing bolt as shown at 22 (see FIGS. 3 and 2).

In operation, a pressure plate with a steel support can be placed on the cylinder be installed, the front edge 23 and the rear edge 24 irregular Have contours (see the dash-dotted lines in Figure 3). The width of the U-profile element (after grinding) should be of a size that is sufficient to accommodate such contours. The grinding is done relative to the insert 14 'in the right lower corner of Figure 2 indicated where the part indicated by dashed lines was ground to the cylinder contour.

A desirable flow course F corresponding to Bigur-4 became obtain, by limiting the course of the river to a space immediately above the Pole pieces, using relatively thin magnets and pole pieces. Optimal results are obtained with pole pieces on the order of 1.6 mm (1/16 ") in width and with permanent magnets on the order of 3.2 mm (1/8") in the thick. Larger dimensions can be allowed, although for best results preferably at least three pole piece magnet combinations per linear inch (2.54 cm) measured axially across the cylinder 10 should be provided.

Numerous advantages can be achieved with the construction according to the invention compared to the washers or rings previously used. A far stronger and more rigid roller results together with an easy assembly, thereby limiting the undesirable distraction or jumping mentioned above. A greater flux density is also achieved, since with the aforementioned arrangement an essential one Contact between the mail pieces and permanent magnets is achievable for what is known Construction was by no means characteristic.

In some cases, an elongated slot, as shown at 26, can be provided, in order to further align the leading and trailing edges of the printing plate to contribute.

With regard to a concise presentation, the invention has only been based on explained in a single embodiment; all of which is not essential to the invention Believed was omitted.

Patent claims

Claims (3)

PATENT CLAIMS Q)) Pressure cylinder for use with thin steel support plates Or the like., characterized by a plate cylinder with a longitudinal slot in the Circumference, the slot having a circumferential extension sufficient therewith both axial edges of this plate come into contact with the slot; a one-piece Insert in this slot, the insert being essentially U-shaped Has element (16) which is received in the slot (12; 13) and out constructed of flow insulating material; through a multitude of axially aligned, at a distance from one another arranged permanent magnets in this element, in which identical pole faces are arranged adjacent to one another and axially transverse to the insert get lost; by a zuagnetisbaren element between adjacent magnets, the protrudes radially outward from these magnets; and by a hardened adhesive, which connects adjacent elements and provides a one-piece construction, wherein the outer surface of the insert is designed according to the cylinder surface; and by devices with which the insert is attached to the cylinder. 2.) Printing cylinder according to claim 1, characterized in that the Insert magnets and the protruding elements are arranged in pairs, the The thickness of the magnets and elements is chosen so that more than three pairs of magnets and Items are arranged per linear inch (2.54 cm). 3.) Printing cylinder according to claim 2, characterized in that the protruding elements have a thickness on the order of about 1.6 mm (1/16) and the magnets are on the order of about 3.2 mm (1/8 ") thick.