JPS5932884B2 - How to assemble the magnet roll - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for assembling a magnet roll used in electronic copying machines, facsimile machines, printers, etc., and more particularly to a method for assembling a magnet roll in which a shaft is fixed to a cylindrical magnet.

2. Description of the Related Art In magnetic brush developing devices and magnetic cleaning devices used in electronic copying machines and the like, devices in which a magnet roll is provided inside a non-magnetic sleeve are used.

As this magnet roll, for example, as shown in FIG. 1, there is used one in which a shaft 2 is fixed to a cylindrical magnet 1 having a plurality of magnetic poles (not shown) on its surface. When assembling a magnet roll using a cylindrical magnet as shown in Fig. 1, conventionally, a shaft 2 whose outer circumferential surface was coated with adhesive 3 was inserted into a cylindrical magnet 1, and then dried to fix the two. Rear magnet 1 (b) Manufactured by grinding the outer circumferential surface 750 However, with this method, if the center of the outer diameter of the magnet and the center of the inner diameter are misaligned and the magnet is deflected, of course, such deflection will occur. Even if there is no difference between the inner diameter of the magnet and the shaft diameter, the bond will be biased to one side, so when looking at the shaft, the outer diameter of the magnet will deviate as if it were deflected, which would increase the cost. There was a problem in that it took a lot of man-hours to grind the outer circumferential surface.Furthermore, in the case of using multi-pole anisotropically oriented magnets, variations in magnetic force appeared.Furthermore, the shaft There were also problems such as a reduction in processing efficiency due to the inability to apply a strong load during processing due to constraints such as the shape.In particular, as shown in Figure 2, when forming a ring with a multi-polar structure, the ring was oriented in the direction of the broken line arrow. When using a oriented magnet 1', it is assumed that the shaft 2' fixed to the inner surface of the magnet 1' is offset downwardly as shown in FIG. 3, for example.

As a result, magnet 1' after how many books were made based on the shaft standard
A schematic view of the oriented portion is shown in FIG. 4, and the magnetic force is high on the side where the shaft is offset, but it is low on the opposite side, resulting in a problem that the uniformity of the magnetic force is secondary. ) An object of the present invention is to provide a method for assembling a magnet roll that eliminates the disadvantages of the above-mentioned prior art and that can be easily processed with a small number of man-hours and that provides a highly accurate magnet roll with less variation in magnetic force. That's true. The details of the present invention will be explained below with reference to the drawings.

5-1 is a sectional view of a magnet roll for explaining one embodiment of the present invention. First, as shown in FIG. 5, the outer peripheral surface of the magnet 1 is ground 5 using a centerless grinder, for example, based on the magnet outer diameter, and then the solid center shaft 4 is fixed to the inner peripheral surface of the magnet 1 with an adhesive 3 or the like. . In this case, the magnet 1 may be ground after the central shaft 4 is fixed. Next, as shown in FIG. 6, using the outer circumferential surface of the magnet opening as a reference plane, a spigot process is performed on both ends of the central shaft 4, and the rotary shafts 5, 5' are attached to the spigot part 4a.
Make sure that it can be loaded. Then, as shown in FIG. 7, rotating shafts 5, 5' are fixed to both ends of the central shaft 4 by adhesive or press fitting, thereby obtaining a magnet roll. Therefore, according to the above method, even if the magnet has a large thickness deviation, the position of the spigot machining is simply changed as shown in FIG. 6, so the machining is extremely easy compared to the conventional method. Furthermore, in the past, it was necessary to use expensive stainless steel for the shaft due to strength issues, but with the present invention, the central shaft only needs to hold the rotating shaft, so only the rotating shaft is made of stainless steel, and the central shaft is made of high-strength stainless steel. Since inexpensive materials such as aluminum or aluminum alloys, which are weaker than stainless steel, can be used, the cost can be reduced. FIG. 8 is a sectional view of a magnet roll showing another embodiment of the present invention, in which a pipe-shaped center shaft 6' is used in place of the solid center shaft in FIG.

In this case as well, the assembly method may be the same as that shown in Figs. 5 to 7. After inserting and fixing the center shaft 6' into the magnet 1, spigot processing is performed, and the rotating shafts 7, 7' are fixed to the spigot part of the center shaft 6. Bye. As described above, according to the present invention, it is possible to obtain a magnet roll that can be processed easily with a small number of processing steps, has high precision, and has little variation in surface magnetic flux density.

Further, according to the present invention, since the central shaft does not require high strength, inexpensive materials can be used, and the magnet roll can be manufactured at low cost.

[Brief explanation of drawings]

Fig. 1 is a sectional view of a conventional magnet roll, Figs. 2 to 4 are schematic diagrams showing a method of assembling a conventional magnet roll when a ring anisotropic magnet is used, and Figs. 5 to 7 The figure is a sectional view of a magnet roll showing one embodiment of the invention, and FIG. 8 is a sectional view of a magnet roll showing another embodiment of the invention. 1: Magnet, 4, 6: Center axis, 5, 5', 7, 7'
:Axis of rotation.

Claims (1)

[Claims] 1 The central shaft is inserted and fixed into the inner surface of a cylindrical magnet whose outer peripheral surface has been previously processed in a specified manner, or the central shaft is inserted and fixed into the inner surface of the cylindrical magnet, and then the central shaft is inserted and fixed onto the outer peripheral surface of the cylindrical magnet. A method for assembling a magnet roll, characterized in that after performing the above processing, a spigot process is performed on both ends of the central shaft based on the outer peripheral surface of the magnet, and a rotating shaft is fixed to each of the spigot parts.