JP2022150077A - Magnet roll, and manufacturing method of magnet roll - Google Patents

Abstract

To provide a magnet roll with satisfactory coaxiality capable of preventing the penetration of the developer into the magnet roll while reducing the manufacturing time of the magnet roll.SOLUTION: The magnet roll includes: a permanent magnet member having multiple magnetic poles; a cylindrical sleeve made of non-magnetic material; and flanges fixed to both edges of the sleeve. In the magnet roll, the permanent magnet member arranged inside the sleeve and the sleeve are rotatable relative to each other. The flange has an annular flange provided on the edge and a knurled portion extending axially from the annular flange. The annular flange and the edge of the sleeve are in contact with each other, and the knurled part and the sleeve are caulked and fixed.SELECTED DRAWING: Figure 2

Description

The present invention relates to a magnet roll used for conveying a magnetic developer and a method for manufacturing the same.

2. Description of the Related Art Magnet rolls are known as means for conveying a magnetic developer and rolls for cleaning in electrophotographic apparatuses, electrostatic recording, and the like.
The magnet roll has a cylindrical sleeve made of a non-magnetic material, a magnet member having a plurality of magnetic poles, and flanges fixed to both ends of the sleeve. It has a rotatable configuration.

As for fixing the sleeve and the flange, a method of fixing them with an adhesive disclosed in Patent Document 1 and a method of mechanically fixing them disclosed in Patent Document 2 are known.

Patent Literature 1 discloses a method of applying an adhesive to the peripheral surface of the flange and fixing it to the sleeve.

Patent Literature 2 discloses a technique of bending a sleeve around the end of a flange and caulking and fixing the sleeve to an edge or chamfer formed at the end of the flange.

JP-A-6-202479 JP-A-2-205874

The technique disclosed in Patent Document 1 has a problem that it takes time to cure the adhesive and wipe off the leaked adhesive.

In the technique disclosed in Japanese Patent Application Laid-Open No. 2002-200000, a gap is generated between the flange and the sleeve at the caulked portion, and the developer (toner) enters the inside of the magnet roll through this gap, which may cause insulation failure. In addition, since the flange ends are crimped, the coaxiality between the flange and the sleeve (the coaxiality of the magnet roll) is generally low, and there are cases where product specifications that require high coaxiality cannot be satisfied.

SUMMARY OF THE INVENTION The present invention has been made in view of such circumstances, and it is an object of the present invention to provide a magnet roll that shortens the manufacturing time of the magnet roll, prevents developer from entering the magnet roll, and has good coaxiality. aim.

A magnet roll according to the present invention has a permanent magnet member having a plurality of magnetic poles, a cylindrical sleeve made of a non-magnetic material, and flanges fixed to both ends of the sleeve, and is arranged inside the sleeve. In the magnet roll in which the permanent magnet member and the sleeve are relatively rotatable, the flange has an annular flange provided at an end and a knurled portion extending axially from the annular flange, The annular collar portion and the end portion of the sleeve are in contact with each other, and the knurled portion and the sleeve are fixed by caulking.

According to the present invention, since the annular flange portion of the flange and the end portion of the sleeve are in contact with each other, it is possible to prevent the developer from entering the magnet roll. In addition, since the sleeve is crimped and fixed to the knurled portion, a magnet roll having good coaxiality can be obtained. Moreover, since it is crimped and fixed, the manufacturing time can be shortened.

The magnet roll according to the present invention is characterized in that the knurls are flat knurls.

According to the present invention, a magnet roll having good coaxiality can be obtained.

The magnet roll according to the present invention is characterized in that the knurling is a twill knurling.

According to the present invention, a magnet roll having good coaxiality can be obtained.

The magnet roll according to the present invention is characterized by having an annular groove portion in the circumferential direction at the center portion in the axial direction of the knurl.

According to the present invention, it is possible to obtain a magnet roll having good coaxiality and having a sleeve and a flange fixed with high strength.

The magnet roll according to the present invention is characterized by having an annular groove portion smaller than the outer diameter of the knurl portion between the annular flange portion and the knurl portion.

ADVANTAGE OF THE INVENTION According to this invention, the knurling process to a flange peripheral surface can be facilitated.

The magnet roll manufacturing method of the present invention includes a cylindrical sleeve made of a non-magnetic material, a permanent magnet member provided inside the sleeve and having a plurality of magnetic poles, and flanges fixed to both ends of the sleeve. In the method for manufacturing a magnet roll having .

According to the present invention, the sleeve can be crimped and fixed to the flange.

The magnet roll manufacturing method of the present invention is characterized in that the roller has an annular projection on the outer peripheral surface of the roller.

According to the present invention, it is possible to obtain a magnet roll with high bonding strength between the sleeve and the flange.

ADVANTAGE OF THE INVENTION According to this invention, while shortening the manufacturing time of a magnet roll, the penetration|invasion of the developer into a magnet roll can be prevented, and a magnet roll with favorable coaxiality can be provided.

FIG. 2 is a diagram showing the configuration of a magnet roll, where A is an axial sectional view and B is an AA sectional view of A. FIG. FIG. 4 is a partial cross-sectional view showing a state in which the sleeve and the flange are crimped according to Embodiment 1, where the flange is shown in a side view and the sleeve is shown in a cross-sectional view. FIG. 10 is a partial cross-sectional view showing a state in which the sleeve and the flange are crimped according to Embodiment 2, the flange is shown in a side view, and the sleeve is shown in a cross-sectional view. 4 is a partial cross-sectional view showing the inside of a dotted line frame C in FIG. 3; FIG. FIG. 11 is a partial cross-sectional view showing a state in which the sleeve and the flange are crimped according to Embodiment 3, the flange is shown in a side view, and the sleeve is shown in a cross-sectional view. FIG. 14 is a partial cross-sectional view showing a state in which the sleeve and the flange are crimped according to Embodiment 4, the flange is shown in a side view, and the sleeve is shown in a cross-sectional view. FIG. 11 is a partial cross-sectional view showing a state in which a sleeve and a flange are crimped according to Embodiment 5, where the flange is shown in a side view and the sleeve is shown in a cross-sectional view; FIG. 11 is a partial cross-sectional view showing a state in which a sleeve and a flange are crimped according to Embodiment 6, where the flange is shown in a side view and the sleeve is shown in a cross-sectional view; FIG. 11 is a partial cross-sectional view showing a state in which a sleeve and a flange are crimped according to Embodiment 7, where the flange is shown in a side view and the sleeve is shown in a cross-sectional view; FIG. 20 is a partial cross-sectional view showing a state in which a sleeve and a flange are crimped according to Embodiment 8, where the flange is shown in a side view and the sleeve is shown in a cross-sectional view; It is a figure which shows an example of the manufacturing method of this invention, A is a partial axial sectional view, B is a side view which looked at A from the arrow D direction. FIG. 4 is a partial axial cross-sectional view (enlarged view) showing another example of the manufacturing method of the present invention;

Hereinafter, the present invention will be described in detail based on the drawings showing its embodiments.
FIG. 1 shows the structure of the magnet roll 1, where A is its axial sectional view and B is its AA sectional view. The magnet roll 1 has a cylindrical sleeve 2 made of a non-magnetic material, a permanent magnet member 3 arranged inside the sleeve, and flanges 4 and 5 arranged at both ends of the sleeve 2 . The flange 4 has an axis of rotation 8 . The flange 4 is rotatably connected to the shaft 6 via a bearing 7 into which the projecting portion 11 of the shaft 6 is inserted. The flange 5 is rotatably connected to the shaft 6 via the thin shaft portion 9 of the shaft 6 and the bearing 7 .

The sleeve 2 is made of a non-magnetic metal material such as an aluminum alloy or non-magnetic stainless steel. The permanent magnet member 3 has a structure in which the shaft 6 (thick shaft portion 10 of the shaft 6) is inserted into the center hole of a cylindrical magnet 200 having a plurality of magnetic poles arranged in the circumferential direction and fixed. . The shaft 6 is made of metal and made of high strength material.

With such a configuration, the sleeve 2 (including the flanges 4 and 5) and the permanent magnet member 3 (including the shaft 6) are relatively rotatable.
Specifically, when the thin shaft portion 9 of the shaft 6 is fixed and the rotating shaft 8 is rotated, the flanges 4 and 5 and the sleeve 2 are rotated, the rotating shaft 8 is fixed, and the thin shaft portion 9 of the shaft 6 is rotated. Then, the permanent magnet member 3 rotates.

The magnet roll 1 is provided parallel to a photosensitive drum (not shown), and the toner (developer) held on the outer peripheral surface of the sleeve 2 is transported onto the electrostatic latent image of the developing portion of the photosensitive drum, and is static. Attached to the electrostatic latent image. At this time, in order to improve the transportability of the developer, the surface of the sleeve 2 may be provided with a plurality of grooves or unevenness arranged in the axial direction, or may be surface-treated.

A brief description will be given of the manufacturing process of the magnet roll 1 configured as described above.

The permanent magnet member 3 uses a magnet 200 such as a sintered ferrite magnet, a ferrite resin-bonded magnet, a rare earth resin-bonded magnet, or a composite magnet thereof. The permanent magnet member 3 may be manufactured by fixing the shaft 6 to the center hole of a cylindrical magnet 200 having a plurality of magnetic poles arranged in the circumferential direction using a known adhesive or the like. Alternatively, the permanent magnet member 3 in which the shaft 6 and the magnet 200 are integrated is produced by supplying a composition of a mixture of resin and magnetic powder around the shaft 6 arranged in a mold, molding it, and magnetizing it. You can

Next, flanges 4 and 5 are fitted to both ends of shaft 6 of manufactured permanent magnet member 3 via bearings 7 and 7, which is inserted into sleeve 2, and both ends of sleeve 2 are crimped. are secured to flanges 4 and 5, respectively.

Next, the caulking structure for fixing the sleeve 2 and the flanges 4 and 5, which is a feature of the present invention, will be described in detail for each embodiment.

Embodiment 1
FIG. 2 is a partial cross-sectional view showing a state in which the sleeve 2 and the flange 4 are crimped. The flange 4 is shown in a side view so that the positional relationship with the sleeve 2 is clear. The sleeve 2 is shown in cross section. The same drawing notation is used in the embodiments described below. Since the flange 5 has the same caulking structure, the description of the flange 5 is omitted.

The sleeve 2 is made of a cylindrical plastically deformable non-magnetic material. A thick portion 13 and a stepped portion 12 connecting the thin portion 14 and the thick portion 13 are formed.

The flange 4 is disc-shaped and has a rod-shaped rotating shaft 8 formed in the center on one side thereof. The flange 4 is formed with an annular flange portion 17, a knurled portion 15, and a reduced diameter portion 16 in this order from the rotating shaft 8 side. The outer diameter of the annular collar portion 17 is larger than the inner diameter of the thin portion 14 of the sleeve 2 and is the same as or slightly smaller than the outer diameter of the sleeve 2 .

A flat knurl parallel to the axial direction of the flange 4 is formed on the knurled portion 15 . The outer diameter of the knurled portion 15 (measured at the top of the flat knurl) is smaller than the inner diameter of the thinned portion 14 of the sleeve 2 .

The end portion of the thin portion 14 of the sleeve 2 is brought into contact with the annular flange portion 17 of the flange 4,
The sleeve 2 and the knurled portion 15 of the flange 4 are crimped and fixed. With such a configuration, the sleeve 2 and the flange 4 are caulked and fixed using the knurled portion 15 as a reference surface, so that a magnet roll having good coaxiality can be obtained. Further, since the annular flange portion 17 of the flange 4 and the end portion of the thin portion 14 of the sleeve 2 are in contact with each other, the toner (developer) is less likely to enter the magnet roll 1 through the gap between the flange 4 and the sleeve 2, resulting in insulation. Defects can be prevented from occurring.

Embodiment 2
FIG. 3 is a partial cross-sectional view showing a state in which the sleeve 2 and the flange 19 are crimped. Also, FIG. 4 shows the inside of the dotted line frame C in FIG.

Embodiment 2 differs from Embodiment 1 in that an annular groove 18 is formed between an annular flange 17 and a knurled portion 25 . The outer diameter of the annular groove 18 is set smaller than the outer diameter of the knurled portion 25 (measured at the top of the knurled portion).

Knurling is performed by cutting or rolling (plastic deformation by a mold). The contact surface of the sleeve 2 may be damaged. If the contact surface is scratched, toner (developer) may enter the inside of the magnet roll from the scratched portion. By forming the annular groove portion 18 between the annular flange portion 17 and the knurled portion 25, the annular flange portion 17 is not damaged by the knurling process, further reducing the possibility of toner (developer) entering the inside of the magnet roll. can do.

Embodiment 3
FIG. 5 is a partial cross-sectional view showing a state in which the sleeve 2 and the flange 20 are crimped.
Embodiment 3 is different from Embodiment 1 in that an annular groove 21 is formed in the axially central portion of the knurled portion 35 . A portion of the annular groove portion 21 having the smallest outer diameter (bottom portion of the groove) is set smaller than the outer diameter of the knurled portion 35 (measured at the top of the knurled portion).

The annular groove 21 is fitted with the annular recess 22 of the sleeve 2 (concave on the outer peripheral surface of the sleeve, convex on the inner peripheral surface of the sleeve) formed by pressing the annular convex portion 110 of the crimping roller 80 in the manufacturing method described later. Thereby, the fixation between the flange 20 and the sleeve 2 becomes stronger.

Embodiment 4
FIG. 6 is a partial cross-sectional view showing a state in which the sleeve 2 and the flange 23 (knurled portion 45) are crimped. The present embodiment is a modification of the third embodiment shown in FIG. 5 (in which the annular groove 21 is formed in the axial central portion of the knurled portion 35) to the second embodiment shown in FIG. An annular groove portion 18 is formed between the portions 25). The fourth embodiment has an effect obtained by combining the functions and effects of the second and third embodiments.

Embodiment 5
FIG. 7 is a partial cross-sectional view showing a state in which the sleeve 2 and the flange 24 are crimped. The fifth embodiment differs from the first embodiment in that the knurled portion 55 is formed with a twilled knurl. By forming the twill knurling, the fixing between the sleeve 2 and the knurling portion 55 becomes stronger.

Embodiment 6
FIG. 8 is a partial cross-sectional view showing a state in which the sleeve 2 and the flange 25 (knurled portion 65) are crimped. This embodiment is a modification of the fifth embodiment shown in FIG. 6 (where the knurled portion 65 is formed with a twill knurl), and the second embodiment shown in FIG. ) in which the annular groove 18 is formed. The sixth embodiment has an effect obtained by combining the functions and effects of the second embodiment and the fifth embodiment.

Embodiment 7
FIG. 9 is a partial cross-sectional view showing a state in which the sleeve 2 and the flange 26 (knurled portion 75) are crimped. The present embodiment is a modification of the fifth embodiment shown in FIG. 7 (where the knurled portion 75 is formed with a twilled knurl), and the third embodiment shown in FIG. 21 is formed). The seventh embodiment has an effect obtained by combining the effects of the third embodiment and the fifth embodiment.

Embodiment 8
FIG. 10 is a partial cross-sectional view showing a state in which the sleeve 2 and the flange 27 (knurled portion 85) are crimped. The eighth embodiment differs from the seventh embodiment in that an annular concave portion 18 is provided as in the second embodiment.
Since the effects of the eighth embodiment are a combination of the effects of the seventh embodiment and the second embodiment, a detailed description thereof will be omitted. This embodiment is a modification of the seventh embodiment shown in FIG. 9 (the knurled portion 85 is formed with a twilled knurl, and the annular groove portion 21 is formed in the central portion of the knurled portion 85 in the axial direction). 2 (in which the annular groove 18 is formed between the annular flange 17 and the knurled portion 85) shown in FIG. The eighth embodiment has an effect obtained by combining the effects of the second embodiment and the seventh embodiment.

FIG. 11 shows an example of the manufacturing method (crimping method) of the magnet roll of the present invention. A is a partial axial cross-sectional view showing a method of caulking the magnet roll, and B is a side view of A as seen from the direction of arrow D. FIG. Description will be made using the magnet roll of the first embodiment.

In the magnet roll manufacturing method of the present invention, a metal crimping roller 50 is pressed against the outer peripheral surface of the magnet roll 1 (the outer peripheral surface of the thin portion 14 of the sleeve 2 ) to crimp the sleeve 2 and the flange 4 .

The crimping roller 50 has an outer peripheral surface 70 , a rotating shaft 90 and an inclined surface 60 . The crimping roller 50 is configured to revolve, rotate, and move in the direction of crimping the magnet roll 1 (in the central axis direction of the magnet roll 1) by a rotation mechanism (not shown).

As shown in FIG. 11A, the magnet roll 1 is moved in the direction of the crimping roller 50 by a moving mechanism (not shown) so that the outer peripheral surface 70 of the crimping roller 50 is aligned with the knurled portion 15 of the flange 4 in the axial direction. The crimping roller 50 is moved toward the axial center of the magnet roll 1 so as to press against the thin portion 14 of the sleeve 2 (crimping operation 1).

Thereafter, as shown in FIG. 11B, the sleeve 2 and the flange 4 are crimped and fixed by rotating the three crimping rollers 50 in the opposite direction (crimping operation 2). Note that the crimping operation 1 and the crimping operation 2 may be performed at the same time.

FIG. 12 shows that the sleeve 2 and the flange 23 are formed by using the flange 23 in which the annular groove 21 is formed in the axially central portion of the knurled portion 23 as in the fourth embodiment (the same applies to the third, seventh, and eighth embodiments). FIG. 10 is a partial axial cross-sectional view showing another example of a manufacturing method for crimping 23 (knurled portion 23).

In this example, the annular concave portion 22 (convex on the inner surface of the sleeve) formed in the thin portion 14 of the sleeve 2 is pushed by the annular convex portion 110 formed on the outer peripheral surface 100 of the crimping roller 80 . It enters into (fits into) the annular groove 21 formed in the central portion of the direction, and the fixation between the flange 23 and the sleeve 2 becomes stronger. The shape of the annular protrusion 110 is not particularly limited as long as the thin portion of the sleeve 2 enters the annular groove 21 and is strongly fastened. For example, in a cross-sectional view, it may swell in an arc shape, or may be rectangular.

The disclosed embodiments are illustrative and not restrictive. The technical scope of the present invention is indicated by the scope of claims, and is intended to include meanings equivalent to the scope of claims and all modifications.

1 magnet roll 2 sleeve 3 permanent magnet members 4, 5, 19, 20, 23, 24, 25, 26, 27 flange 6 shaft 7 bearing 8 rotating shaft (shaft)
9 Thin shaft (shaft)
10 thick shaft (shaft)
11 protrusion (shaft)
12 step (sleeve)
13 thick part (sleeve)
14 thin part (sleeve)
15, 25, 35, 45 knurling part (flat knurling)
16 reduced diameter part (flange)
17 Annular collar (flange)
18 Annular groove (flange)
21 annular groove (flange)
22 Annular concave portions 50, 80 Crimping rollers 55, 65, 75, 85 Knurling portion (twill knurling)
60 Inclined surface (caulking roller)
70, 100 Peripheral surface (caulking roller)
90 Rotating shaft (crimping roller)
110 Annular protrusion (caulking roller)
200 magnet

Claims (7)

A permanent magnet member having a plurality of magnetic poles, a cylindrical sleeve made of a non-magnetic material, and flanges fixed to both ends of the sleeve, the permanent magnet member disposed inside the sleeve and the In the magnet roll in which the sleeve and the sleeve are relatively rotatable, the flange has an annular flange provided at the end and a knurled portion extending axially from the annular flange, and the annular flange and the end of the sleeve A magnet roll, wherein the knurled portion and the sleeve are fixed by caulking. 2. A magnet roll according to claim 1, wherein said knurled portion comprises a flat knurled portion. 2. A magnet roll according to claim 1, wherein said knurled portion comprises a twilled knurl. 4. The magnet roll according to any one of claims 1 to 3, wherein the knurled portion has an annular groove portion in a circumferential direction at an axial center portion thereof. 5. The magnet roll according to claim 1, further comprising an annular groove portion smaller than the outer diameter of the knurled portion between the annular flange portion and the knurled portion. A method for manufacturing a magnet roll having a cylindrical sleeve made of a non-magnetic material, a permanent magnet member provided inside the sleeve and having a plurality of magnetic poles, and flanges fixed to both ends of the sleeve, wherein the sleeve comprises: A method of manufacturing a magnet roll, wherein the sleeve is crimped and fixed to the flange by pressing a set of three rollers against the peripheral surface of the roller and causing the rollers to rotate and revolve at the same time. 7. The method of manufacturing a magnet roll according to claim 6, wherein the roller has an annular projection on the outer peripheral surface of the roller.

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