JPH0228729B2 - JISEITAIROORUNOSURIIBUNOKASHIMEHOHO - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for caulking a sleeve of a magnetic roll used in a PPC (electrophotographic copying machine) or the like. More specifically, the present invention relates to a method for caulking a sleeve of a magnetic roll in which a caulked portion of the sleeve is fixed without causing distortion on the surface of a non-magnetic flange.

Conventionally, the methods for caulking sleeves of magnetic rolls include a press method in which a caulking jig with a constant caulking angle that matches the inclination angle of the flange is statically pressed against the caulking part of the sleeve, and a press method that has a constant caulking angle. A dynamic rolling head method was used in which a caulking jig, in which multiple rollers are arranged to rotate symmetrically toward the tip of the jig, rotates while pressing against the caulked portion of the sleeve. . However, when the material of the sleeve becomes hard, the former press method tends to cause the sleeve to separate from the flange surface due to the strain generated near the caulked part, as shown in Figure 1a, while the latter rolling method tends to separate the sleeve from the flange surface, as shown in Figure 1a. In order to generate a radial protrusion as shown in Figure 1b at the bent portion of the sleeve due to the strain generated near the caulked portion, a high-density magnetic roll is manufactured in which the caulked portion of the sleeve is brought into close contact with the flange surface. There was a drawback that I couldn't do it.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a method for caulking a sleeve of a magnetic roll by using an improved die (caulking jig) to tightly adhere the sleeve to a non-magnetic flange. purpose.

The method for caulking the sleeve of a magnetic roll according to the present invention will be explained based on the embodiments shown in FIG. 2 and subsequent figures. Note that this invention is not limited by this.

FIG. 2 shows a case where the non-magnetic sleeve 6 is caulked by a press method. The cylindrical magnet 2 is rotatably held on a non-magnetic flange 5 via a bearing 4 by a shaft 3 projecting outward from its main shaft end, and is held in place by a recess 2a at its center end. The non-magnetic flange 5' is rotatably held via a shaft 3' fixed to the magnetic flange 5'. The outer diameter of the non-magnetic flanges 5, 5' at both ends is slightly larger than the outer diameter of the cylindrical magnet body 2, and the caulked portions 6a, 6a' of the sleeve 6 are attached to the outer peripheral surfaces of the non-magnetic flanges 5, 5'. It is mounted so as to protrude slightly outward from the inclined portions 5a, 5a' of the outer end surface of the slanting angle θ ₀ . In order to facilitate caulking, it is preferable to provide grooves 30 and tapered portions 31 as shown in FIG. 6 in the caulking portions 6a, 6a'.

At positions facing both end surfaces of the magnetic roll 1,
The dies 7, 8 are equipped with oil-free metal 19, 19', which are provided with holes 9, 9' into which the shafts 3, 3' can be inserted.
Each is installed.

As shown in detail in FIG. 3, the caulking curved surfaces 10 of the dies 7 and 8 include a first curved surface _10a having an angle θ ₁ greater than or equal to the caulking angle θ ₀ and a second curved surface having an angle θ ₂ less than the caulking angle θ 0. 10b are smoothly connected to each other at a contact point on an extension line of the plate thickness portion L of the sleeve 6 attached to the outer peripheral surface of the flange 5. More preferably, the first curved surface 10a and the second curved surface 10b are smoothly connected toward the outside of the center of the plate thickness portion L. The radius of curvature R of the connecting part at this time
is determined in the range from the sleeve plate thickness L to the length W of the caulked portion of the sleeve 6. The dimensions of the caulking surface 10 explained above can be defined in more detail using mathematical formulas with reference to the symbols shown in FIG. 3, as follows.

θ ₁ ≧θ ₀ ………(i) θ ₂ <θ ₀ Preferably θ ₂ is 5 ⁰ ~ _{θ 0} /2 ………(ii) D ₃ = D ₁ −L/2 ~ D ₁ (However, D ₁ is the outer diameter of the sleeve) ......(iii) R = L ~ W ......(iv) D ₄ > D ₁ (However, D ₄ is the die opening diameter) ...... (v) Normally θ ₀ > 5 ⁰ ......(vi) A die 7 having a caulking curved surface 10 as described above,
8 to press the sleeve 6 attached to the outer periphery of the non-magnetic flanges 5, 5' from the left and right directions as shown in FIG.
a, 6a' are the first curved surfaces 10a, 10 of the dice 7, 8
First, it comes into contact with the connection portion between a and the second curved surfaces 10b, 10b. However, this abutting portion is located on the outside of the center of the plate thickness portion L of the sleeve 6, and its radius of curvature R is within the range from the plate thickness L to the length W of the caulked portions 6a, 6a'. The caulking portions 6a, 6a' of the flange 5 are formed by the second curved surfaces 10b, 10b, which are equal to or less than 1/2 of the caulking angle θ ₀ of the flange 5.
A first curved surface 1 having an angle θ ₁ greater than or equal to θ ₀ while being prevented from causing separation as shown in Figure a.
Non-magnetic flanges 5, 5' by 0a and 10a
are closely integrated into the inclined portions 5a and 5a' of the
A magnetic roll 1 is manufactured.

FIGS. 4 and 5 are a left side view and a front view of the die 11 used for rolling head type caulking. In this die 11, a bearing is attached to each shaft 12 in the radial direction at each notch 11b of a rectangular parallelepiped formed on the outside of each side of an equilateral triangle 11a at the tip.
A roll 14, which is rotatably held via a roller 3, is attached. Each shaft 12 is fixed to the outer peripheral surface of the die 11 with a nut 17 so as to come into contact with a steel ball 16 inserted into a hole 15 provided in a direction perpendicular to each side of the equilateral triangle 11a. 18 is a snap ring inserted between the inner surface of the notch 11b and the end surface of the bearing 13. At the center of the end face of the die 11, a shaft insertion hole 20 in which an oil-less metal 19 is fitted is provided in the length direction.

In this case, the caulking curved surface 21 is formed as a concave curved surface adjacent to the disc-shaped portion 14a of the roll 14 and toward the center of the die 11. Caulking curved surface 21
is a first curved surface 21a having a caulking angle θ ₁ larger than θ ₀ toward the center of the die 11, and a disk-shaped portion 14.
The second curved surface 21b having an angle θ ₂ smaller than the caulking angle θ ₀ on the a side is smoothly connected with the radius of curvature R at the contact portion with the sleeve 6.

Die 1 having a caulking curved surface 21 as described above
1 and 11, and press the sleeve 6 attached to the non-magnetic flanges 5 and 5' from left and right while rotating them, for the same reason as explained in the press method above. Thus, a non-magnetic roll 1 was manufactured in which the sleeve 6 was closely integrated with the surface of the flange 5 at once without causing distortion as shown in FIG. 1b near the caulked portions 6a and 6a' of the sleeve 6. can do.

As is clear from the above explanation, according to the present invention, the first curved surface having an angle greater than or equal to the crimping angle of the flange and the second curved surface having an angle smaller than the crimping angle can be smoothly formed at the portion where the sleeve contacts the sleeve. By using connected dies, it is possible to provide a magnetic roll in which the sleeve is closely integrated with the surface of the flange.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing the drawbacks when using a conventional die, a is a press method, b is a rolling head method, and Fig. 2 is a sleeve of the magnetic roll of the present invention manufactured by a press method. FIG. 3 is a cross-sectional view of the main part showing the shape of the die corresponding to the sleeve crimping part, FIG. 4 is a side view of the rolling head type die,
FIG. 5 is a longitudinal cross-sectional view of the same essential part, and FIG. 6 is an explanatory diagram of the structure of the tip end of the sleeve. 1... Magnetic roll, 2... Cylindrical magnet,
5', 5...Non-magnetic flange, 6...Sleeve,
6a, 6a'... caulking portion, 7, 8... die (caulking jig), 10... caulking surface, 10a... first curved surface, 10b... second curved surface, θ ₀ ... caulking angle, 11... ...Dice (caulking jig), 21a...
First curved surface, 21b...second curved surface.

Claims (1)

[Claims] 1. A magnetic material in which a cylindrical magnet is rotatably held between non-magnetic flanges at both ends, and a non-magnetic sleeve is fixed by caulking to the outer periphery of the non-magnetic flange so as to contain the cylindrical magnet. Using a die which is a body roll and has a first curved surface having an angle equal to or greater than the sleeve swaging angle and a second curved surface having an angle smaller than the swaging angle smoothly connected at the part that contacts the sleeve, A method for caulking a sleeve of a magnetic roll, characterized in that a caulking part of the sleeve is fixed to a magnetic flange without distortion.