JPH0432691Y2 - - Google Patents

Description

[Detailed description of the invention] Field of application This invention relates to the improvement of permanent magnet rolls for electrostatic development used in applications such as electrostatic transfer type electrophotographic copying machines and printers. The present invention relates to a permanent magnet roll for electrostatic development that is integrated with a flange member to improve assembly ease and assembly accuracy.

BACKGROUND ART A permanent magnet roll for electrostatic development has a magnet structure built in a non-magnetic cylindrical sleeve (hereinafter simply referred to as a sleeve) so as to be rotatably supported by a rotating shaft.

In the magnet structure, for example, a plurality of permanent magnets are arranged in the axial direction at radial positions from the shaft center, are supported by non-magnetic flange members (hereinafter simply referred to as flange members) fixed to both open ends of the sleeve, and are separated from each other. It is built in such a way that it can rotate freely relative to the sleeve which is pivotally supported by the sleeve.

This fixing of the sleeve and flange member requires high bonding strength since they are mutually rotatable and require high speed rotation, but on the other hand, there are problems such as complicated assembly such as bonding process. It was hot.

In order to solve the above problem, the applicant first developed a structure in which the sleeve and one flange member were integrated by deep drawing or impact forming, that is, as shown in FIG. We proposed a permanent magnet roll for electrostatic development in which the end is integrally molded with a flange member with a recess 2 for bearing insertion inside (Utility Model Application No. 147216/1983), which improved the bonding strength, halved the bonding process, and We were able to shorten assembly time and improve the work environment.

However, in recent years, the demand for smaller and lighter permanent magnet rolls for electrostatic development has been increasing, and the gap between the permanent magnet surface of the magnet structure and the inner peripheral surface of the sleeve has become extremely small. In order to ensure and maintain smooth relative rotation between the sleeve and the magnet structure, there has been a strong demand for improvement in the dimensional accuracy of the bearing fitting recess 2.

The recess 2 of the sleeve 1 having the configuration shown in FIG. 5 depends on the processing accuracy during molding, and it is difficult to ensure the required high precision. This was extremely difficult because it had a small diameter and was located at the bottom of the long sleeve 1.

Purpose of the invention The purpose of this invention is to create a permanent magnet roll for electrostatic development that is inexpensive and easy to manufacture.In particular, it is possible to simplify the fixation between the sleeve and the flange member, and to improve the dimensional accuracy of each part in order to improve rotational accuracy. The object of the present invention is to provide a permanent magnet roll for electrostatic development with a structure that can improve the performance of the electrostatic development.

Structure and effect of the invention This invention has non-magnetic flange members disposed at both ends of a non-magnetic cylindrical sleeve, and a magnet structure is built coaxially and relatively freely rotatable within the non-magnetic cylindrical sleeve. In a permanent magnet roll for electrostatic development, the sleeve is a cylindrical sleeve in which one end of the sleeve is integrated with a flange member at the end, and a small diameter opening is formed at the axial center position of the flange member, and the small diameter opening is A permanent magnet roll for electrostatic development is characterized in that an oil-impregnated metal bearing or a bearing support member for fitting and supporting the bearing is caulked and fixed.

In this invention, a cylindrical sleeve in which one end of the sleeve and a flange member at that end are integrated, and a small diameter opening is provided at the axial center position of the flange member, can be easily formed by deep drawing, impact forming, etc. It can be obtained with high dimensional accuracy.

Further, as shown in the examples, the oil-impregnated metal bearing that is caulked and fixed to the small diameter opening, or the bearing support member that fits and supports the bearing, can have various configurations depending on the method of supporting the sleeve and the magnet structure, the form thereof, etc.
Any configuration, shape, or material may be used as long as it has a dimensional accuracy that allows it to fit into and abut the small-diameter opening that is formed with high precision for positioning, and can be fixed by caulking. It may be.

By having the above configuration, the bonding strength is improved,
It is possible to reduce the gluing process by half, shorten the assembly time, and improve the dimensional accuracy of the bearing part or bearing storage part to improve rotational accuracy without sacrificing the effect of improving the working environment. A permanent magnet roll for development can be obtained.

Disclosure Based on Drawings of the Invention This invention will be described in detail below based on examples.

FIG. 1 is a cross-sectional explanatory view of a permanent magnet roll according to this invention. FIG. 2 is an explanatory side view of the cylindrical sleeve according to this invention. FIGS. 3 and 4 are cross-sectional explanatory views showing other permanent magnet rolls for electrostatic development according to this invention.

The permanent magnet roll for electrostatic development based on this invention is
Within the non-magnetic cylindrical sleeve 10 is a magnet arrangement 19.
is built in so as to be relatively rotatable while being pivotally supported by the rotating shaft 20, and the magnet structure 19 has a plurality of rod-shaped permanent magnets arranged in the axial direction at radial positions from the center of the rotating shaft 20, although not shown. be.

The cylindrical sleeve 10 is made by integrating a cylindrical sleeve and a flange part 11 by impact molding, and has a small diameter opening 1 at the axial center of the flange part 11.
2 have been established.

Furthermore, four small protrusions 13 are protruded from the small diameter opening 12 to prevent the bearing support member 14 which is caulked and fixed therein from being bitten and rotated.

The bearing support member 14 shown in FIG.
A bearing fitting recess 18 is integrally formed with high dimensional accuracy at the axial center position of the protrusion 17 and the protrusion 17 side, which are press-fitted and fixed by caulking.

The above bearing support member 14 is the cylindrical body sleeve 1
The bearing 21 is press-fitted into the small diameter opening 12 of 0 and fixed by caulking, and the bearing 21 is fitted into the bearing fitting recess 18.
The magnet structure 19 is inserted into the inside of the sleeve 10 from the open end, and the rotating shaft 20 on the insertion tip side is pivotally supported by the bearing 21 of the bearing fitting recess 18, and further, on the open end side of the sleeve 10, Bearing 2 at the shaft center
1 is fitted into the flange member 22, and the rotating shaft 20 at the other end of the magnet structure 19 is fixed.

As mentioned above, it is easy to assemble the permanent magnet roll for electrostatic development according to this invention, and furthermore, since the bearing support member 14 and the small diameter opening 12 are both molded with high dimensional accuracy, it is easy to caulk and fix. The assembly precision is high, and the shaft support of the magnet component 19 and the shaft support of the cylindrical sleeve 10 are extremely precise.
Provides smooth rotation.

The permanent magnet roll for electrostatic development shown in FIG. 3 has a structure in which a bearing support member 23 which is caulked and fixed to the small diameter opening 12 of the cylindrical sleeve 10 pivotally supports the rotating shaft 20 of the magnet structure 19. It consists of an annular collar portion 24 into which a bearing 21 is fitted into the core, and a caulking protrusion 25.

The configuration of FIG. 4 is similar to that of FIG.
9, and the oil-impregnated metal bearing is directly caulked and fixed to the small-diameter opening of the flange. A flange portion 27 that contacts the flange portion 11 of the cylindrical sleeve 10 and a projection portion 28 that is caulked and fixed to the small diameter opening portion 12 are formed on the cylindrical sleeve 10 .

Also in the case of FIGS. 3 and 4, the cylindrical sleeve 10
and bearing support members 23, 26, assembly is easy, and bearing support members 23, 26 and small diameter opening 12
Since both are molded with high dimensional accuracy, the assembly accuracy by caulking and fixing is high, and the shaft support of the magnet component 19 and the shaft support of the cylindrical sleeve 10 are extremely accurate, resulting in smooth rotation. .

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional explanatory view of a permanent magnet roll according to this invention. FIG. 2 is an explanatory side view of the cylindrical sleeve according to this invention. FIGS. 3 and 4 are cross-sectional explanatory views showing other permanent magnet rolls for electrostatic development according to this invention. FIG. 5 is a longitudinal cross-sectional view of a conventional integrally molded sleeve. 10...Cylindrical body sleeve, 11...Flange portion, 12...Small diameter opening, 13...Small protrusion, 1
4, 23...Bearing support member, 15...Shaft portion, 1
6, 27... Flange, 17, 25, 28... Protrusion, 18... Bearing fitting recess, 19... Magnet structure, 20... Rotating shaft, 21... Bearing, 22... Flange member, 24...Annular collar portion, 26...Oil-impregnated metal bearing.

Claims (1)

[Scope of utility model registration request] A permanent magnet roll for electrostatic development, in which non-magnetic flange members are arranged at both ends of a non-magnetic cylindrical sleeve, and a magnet structure is coaxially and relatively rotatably built into the non-magnetic cylindrical sleeve, The sleeve is formed into a cylindrical sleeve by integrating one end of the sleeve with a flange member at the end and having a small diameter opening at the axial center position of the flange member, and an oil-impregnated metal bearing or a bearing is fitted into the small diameter opening. A permanent magnet roll for electrostatic development, characterized in that a supporting bearing support member is caulked and fixed.