JP2002139025A - Roller for electronic apparatus and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic apparatus roller and an image forming device with an easy manufacture, a low cost, a high strength and a high accuracy. SOLUTION: A heating roller 12 used for a fixing part of the image forming device is provided with a roller body 14 made of an aluminum alloy material and formed into a thin long size cylindrical shape; and a short size cylindrical body 16 disposed at both end inner periphery parts 14A of the roller body 14 and reinforcing both ends of the roller body 14. The short size cylindrical body 16 is fixed to both end inner periphery parts 14A of the roller body 14 by a press-fitting.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roller for an electronic device and an image forming apparatus which have a predetermined strength and accuracy while reducing the cost.

[0002]

2. Description of the Related Art Conventionally, stainless steel, aluminum alloys, copper-based alloys, and the like have been used as materials for electronic device rollers used in electronic devices such as image forming apparatuses. Rollers for electronic devices made of stainless steel or a copper-based alloy have high strength and excellent heat resistance, but are difficult to process, and have a large specific gravity and are difficult to reduce in weight.

On the other hand, rollers for electronic devices made of an aluminum alloy have a small specific gravity, so that the weight can be reduced only by using them. For this reason, in a roller for electronic equipment which requires high heat resistance, a high-strength aluminum alloy such as A5052, which is a low magnesium alloy (an aluminum alloy having a magnesium content of about 4% or less), which is relatively easy to process, is used. An extruded mandrel pipe is used by drawing.

[0004]

However, high-strength aluminum alloys require not only many steps for extrusion and drawing but also relatively difficult precision machining and insufficient mechanical strength. It is necessary to be thick, which causes an increase in cost, and there is a limit to weight reduction. Further, in the case of the heating roller, there is a problem that the heat conductivity cannot be improved because the thickness cannot be reduced.

[0005] As a countermeasure, a countermeasure such as using a roller made of stainless steel or a copper-based alloy having excellent mechanical strength has been taken. However, in this case, the weight cannot be reduced, and the rotational accuracy and the bias are not improved. The meat, roundness, straightness, deflection accuracy, and the like become insufficient, and it cannot be manufactured at a low cost, and processing costs are high, resulting in high costs.

SUMMARY OF THE INVENTION The present invention has been made in view of the disadvantages of the prior art, and has as its object to provide a roller and an image forming apparatus for an electronic device which are easy to manufacture, low in cost, and have high strength and high accuracy. Is to provide.

[0007]

According to a first aspect of the present invention, there is provided a roller for an electronic apparatus according to the present invention, wherein the roller body is a long cylindrical roller body formed of metal, and the roller body is disposed at an end of the roller body. And a short cylindrical body that reinforces the end of the above.

Accordingly, according to the first aspect of the present invention,
By disposing a short tubular body for reinforcement at the end of a long tubular roller body made of metal, the roller body can be reinforced. As a result, the roller for an electronic device can be reinforced without increasing the thickness of the roller body. Therefore, a high-strength, high-precision roller for an electronic device that is easy to manufacture, low in cost, and high in strength can be obtained.

According to a second aspect of the present invention, there is provided a roller for an electronic device according to the present invention, which is formed of an aluminum alloy material, is heated by a heat source and driven and rotated, and an end of the roller body. And a short tubular body disposed at the portion for reinforcing an end of the roller body.

Therefore, according to the second aspect of the present invention,
The roller body can be reinforced by disposing the short tubular body at the end of the roller body made of an aluminum alloy material. As a result, the roller for an electronic device can be reinforced without increasing the thickness of the roller body. For this reason, it is possible to obtain a high-precision, high-precision roller for an electronic device that is easy to manufacture, low in cost, and high in strength. In addition, the heat conductivity can be improved by reducing the thickness, so that the starting power and the standby power can be significantly reduced in cost, and the temperature rise time can be significantly reduced.

According to a third aspect of the present invention, in the roller for an electronic device according to the second aspect, the aluminum alloy material contains 4.1 to 5.6% by weight of magnesium, and the roller main body includes: After the ERW process, a drawing process is performed.

Therefore, according to the present invention described in claim 3, in addition to the contents described in claim 2, the aluminum alloy material contains 4.1 to 5.6% by weight of magnesium, and Since the roller body is manufactured by drawing after ERW processing, it has high mechanical strength in material, can be thin, hardly causes intergranular corrosion and stress corrosion, and is not brittle in material By so-called high-strength aluminum alloy, pipes are formed by ERW processing that can be processed more easily, and this is further combined with drawing processing to obtain uneven thickness, roundness, straightness, deflection accuracy, etc. of ERW pipes. , The roller for electronic devices having a small diameter can be easily and easily manufactured.

According to a fourth aspect of the present invention, in the electronic device roller according to the second or third aspect, the roller body has a thickness of 0.2 to 1.0 mm and an outer diameter of 45 mm.
It is characterized by being not more than φ.

Therefore, according to the present invention described in claim 4, in addition to the contents described in claim 2 or 3, the roller body has a thickness of 0.2 to 1.0 mm and an outer diameter of 0.2 to 1.0 mm. 45mm
Because it is less than φ, it is possible to weaken the magnetic force of the built-in magnet when using it for a magnet roller, and when using it for a heating roller,
The temperature characteristics can be improved without delaying the response of the roller surface temperature to the heating element.

According to a fifth aspect of the present invention, in the roller for an electronic device according to any one of the first to fourth aspects, a convex portion for preventing heat radiation is formed on an inner peripheral portion of the short tubular body. It is characterized by having been done.

Therefore, according to the present invention described in claim 5, in addition to the contents described in any one of claims 1 to 4, a protrusion for preventing heat radiation formed on the inner peripheral portion of the short tubular body. The portion makes it difficult for the high-temperature air inside the roller for the electronic device to flow out, so that the heat retaining property of the roller for the electronic device can be improved.

According to a sixth aspect of the present invention, there is provided an image forming apparatus according to the first aspect, wherein the electronic device roller according to the first to fifth aspects is used in a fixing unit.

Therefore, according to the present invention, it is easy to manufacture a roller for an electronic device used in a fixing section, and it is possible to obtain a high-strength and high-precision roller for an electronic device which is low in cost. . Further, the temperature characteristics of the fixing unit can be improved.

According to a seventh aspect of the present invention, in the image forming apparatus according to the sixth aspect, conductive silicone is applied to an end face of the pressure roller pressed by the roller body.

Therefore, according to the invention described in claim 7,
In addition to the contents described in claim 6, the static electricity charged on the roller body can be discharged via the conductive silicone applied to the end surface of the pressure roller.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 to 5 show a fixing roller of an image forming apparatus to which a roller for an electronic apparatus according to a first embodiment of the present invention is applied.

As shown in FIG. 2, a heating roller 12 of the fixing unit 10 includes a roller body 14 formed of an aluminum alloy material and formed in a thin and long cylindrical shape, and a roller body 14.
The roller body 1 is disposed at the inner peripheral portions 14A at both ends of the roller body 1 respectively.
And a short cylindrical body 16 for reinforcing both end portions of the cylindrical member 4.
Further, a cross-linked PTF is provided on the operation surface 14F of the roller body 14.
A fluorine resin 18 such as E is applied.

As shown in FIG. 1, the short cylindrical body 16 is fixed to the inner peripheral portions 14A of both ends of the roller body 14 by press fitting. In addition, ring-shaped bearings (not shown) are provided at the outer peripheral portions 14B at both ends of the roller body 14, and the roller body 14 is supported by the fixing unit body by these bearings.

As shown in FIG. 3, a notch 20 extending along the axial direction of the roller body 14 is formed on the left end side of the roller body 14, and a transmission gear 22 is correspondingly formed.
An engagement projection 24 is provided to protrude on the inner peripheral side of the projection. When the engaging projection 24 of the transmission gear 22 is engaged with the notch 20 and a driving force is transmitted to the transmission gear 22 from the outside, the heating roller 12 rotates with the rotation of the transmission gear 22. It is configured to rotate integrally with the transmission gear 22.

As shown in FIG. 4, a heating element 30 such as a halogen lamp is inserted into the heating roller 12, and the heating roller 12 is heated from the inside by the heat generated by the heating element 30. I have.

On the other hand, below the heating roller 12, a pressure roller 34 formed of a silicone rubber, which is a low-hardness rubber material, in a cylindrical shape so as to be wound around a metal support shaft member 32, The pair of heat-resistant cylinders 36 made of resin are fitted to the support shaft members 32 protruding from both ends of the pressure roller 34 so as to extend in parallel with the axial direction of the heating roller 12. Heat-resistant cylinders 36 are disposed at both ends of the pressure roller 34, respectively.

The outer diameter of the heat-resistant cylinder 36 is formed to be slightly smaller than that of the pressure roller 34. Further, both end portions of the support shaft member 32 are rotatably supported by U-shaped bearings 42 attached to the upper end portion of the coil sprocket 40. For this reason, the pressure roller 34 is elastically supported by the coil sp cylinder 40 via the bearing 42 and the support shaft 32 while the heating roller 12 is
, And integrally rotates with the rotation of the heating roller 12. At this time, since the outer diameter of the heat-resistant cylinder 36 is slightly smaller than the outer diameter of the pressure roller 34, the pressing force by the coil sp cylinder 40 is applied, as shown in FIG. The roller 34 is deformed, and the heat-resistant cylinder 36 comes into contact with the heating roller 12 so that the nip width can be set to a certain range.

As described above, the heating roller 12 and the pressure roller 3
Copy paper 4 on which the toner image shown in FIG.
6 is inserted, the heating roller 12 and the pressing roller 34 are pressed against each other by the coil sp cylinder 40 so that the copy sheet 46 is held between the heating roller 12 and the pressing roller 34, and these rollers rotate. As a result, the copy paper 46 is heated and the toner is fixed on the copy paper 46.

Further, as shown in FIG.
The conductive silicone 35 is applied to the end surface 34A of the fourth roller 4 so that the static electricity charged on the roller body 14 of the heating roller 12 can be discharged through the conductive silicone 35.

The material used for the roller body 14 of the present embodiment is an annealed material (tempered O material) such as A5083 or A5182 containing 4.1 to 5.6% magnesium or unannealed (H Material) Use aluminum alloy.

Here, when the magnesium content is less than 4.1%, the mechanical strength of the material is low, and the magnet roller or the heating roller used in the apparatus of the type combining the heating roller and the pressure roller is: In order to improve the mechanical strength, it is necessary to sacrifice weight reduction by making the roller thicker. It is not preferable that the thickness of the roller is thick, because the response of the roller surface temperature with the heating element is delayed in the heating roller. In addition, when the thickness is increased, the thickness of the roller is unbalanced, the roundness, the straightness, the deflection accuracy, and the like are adversely affected.

On the other hand, in an aluminum alloy having a magnesium content of more than 5.6%, an aluminum-magnesium intermetallic compound (eg, Mg ₂ Al ₃ ) is liable to precipitate at the grain boundaries, causing intergranular corrosion and stress corrosion. This is not preferable because it tends to occur, and the material becomes brittle, and workability and mechanical strength are reduced.

It is to be noted that the aluminum alloy according to the present invention contains 0.4 to 1.0% by weight of manganese, 0.05 to 0.25% by weight of chromium, etc. in order to improve plastic workability and mechanical properties. May be a high-strength aluminum alloy to which a small amount of the above metal is added.

Since the high-strength aluminum alloy containing 4.1 to 5.6% of magnesium has high strength, it is difficult, if not impossible, to manufacture a pipe by extrusion. Therefore, in the present embodiment, the roller body 14 is formed by processing the strip into a pipe shape by the electric resistance sewing process, and further performing the drawing process.

That is, in the present embodiment, a high-strength aluminum alloy, which is very difficult to manufacture by extrusion, is made into a pipe by electric resistance welding, which can be processed more easily, and this is further combined with drawing. Thus, the accuracy of the ERW pipe, such as uneven thickness, roundness, straightness, and deflection accuracy, is improved, and the roller body 1 having a small diameter can be easily and easily formed.
4 can be manufactured.

Further, the pipe after the drawing process is subjected to a PA process (heat treatment process of the pipe) and then to a finish drawing process, whereby uneven thickness of the roller, roundness, straightness,
It greatly improves the deflection accuracy and further enhances the performance as a roller for electronic equipment.

In addition, the processing rate of the above-mentioned drawing is as follows.
It is 10 to 40%, preferably 15 to 35%, more preferably 20 to 30%. When finish drawing is not performed, it is generally necessary to perform drawing at a high processing rate.
If the processing rate is less than 10%, the influence of distortion or the like in the electric resistance sewing cannot be completely eliminated, and the accuracy such as uneven thickness and roundness tends to be insufficient. Making the processing rate over 40% not only results in large energy loss, but also
Distortion in the drawing process is newly generated, and accuracy such as uneven wall thickness, roundness, straightness, and deflection accuracy of the roller is reduced.

On the other hand, the processing rate of the finish drawing is 1 to
It is about 10%, preferably about 3 to 7%. Although it may not be necessary when the previous drawing process is performed sufficiently effectively, it is preferable to perform this in order to produce a highly accurate electronic device roller. When a certain degree of precision is obtained in the former drawing process, the processing ratio of the finish drawing process may be small, and when it is insufficient, it is necessary to increase the processing ratio. The pipe created in this way is the roller body 14
, And is processed into a roller body 14 (for example, a wall thickness of 0.2 to 1.0 mm and an outer diameter of 45 mmφ or less).

When performing the finish drawing, since the rotation is smooth and the eccentricity can be easily reduced, an ideal roller shape can be obtained.

The inner peripheral portions 14A at both ends of the roller body 14
In consideration of contact with the roller body 14, the material of the short cylindrical body 16 arranged in each of the above is a polyimide equivalent or a phenolic thermosetting resin or the like which has excellent heat resistance and has a high temperature dimension. Materials that can ensure accuracy are conceivable.

Next, the operation of the present embodiment will be described.

The roller body 14 according to the present embodiment is made of a high-strength aluminum alloy containing 4.1 to 5.6% of magnesium by electric resistance welding and drawing (and, if necessary, PA processing,
A roller core type roller manufactured from a pipe manufactured by performing a finish drawing process.
The short cylindrical bodies 16 are respectively arranged on the inner peripheral portions 14A at both ends of the cylindrical member. For this reason, the strength around the both ends of the thinned roller body 14 is improved.

That is, with the heat-resistant cylinder 36 being installed on the pressure roller 34 in order to form a predetermined nip width, the pressing force must be set to a predetermined value or more. Therefore, it is necessary to increase the set value of the pressing force, which is the load of the coil sp cylinder 40, in consideration of the manufacturing variation of the coil sp cylinder 40. And, as the pressing force of the coil sp cylinder 40 is increased,
Although the strength of both ends of the heating roller 12 becomes a problem, the above-described structure prevents the heating roller 12 from being deformed. Further, the strength of the portion of the heating roller 12 that engages with the transmission gear 22 is also improved.

Accordingly, the heating roller 12 of the present embodiment is easy to form and inexpensive. Further, even if the roller main body 14 is thin and lightweight, it has sufficient strength as the heating roller 12, can improve abrasion resistance, and can be a highly accurate roller. The roller body 14
Is thin, so that the thermal conductivity can be improved,
It is possible to greatly reduce the cost of starting power and standby power, significantly reduce the time for starting up the temperature, and significantly reduce the time required for initial use.

When the roller body 14 is used as a magnet roller, the magnetic force of the built-in magnet can be reduced.

In this embodiment, as shown in FIG. 5, the static electricity charged on the roller body 14 of the heating roller 12 is discharged through the conductive silicone 35 applied to the end face 34A of the pressure roller 34. be able to.

In this embodiment, the short cylindrical body 16 is fixed to the inner peripheral portions 14A of both ends of the roller body 14 by press-fitting. However, instead of press-fitting, as shown in FIG.
4 and the end surface 16A of the short cylindrical body 16 are welded, and the short cylindrical body 16 is connected to the inner peripheral portions 14A at both ends of the roller body 14.
May be fixed.

Further, as shown in FIG.
4 and the outer peripheral portion 16B of the short cylindrical body 16 may be spot-welded at the hitting point P to fix the short cylindrical body 16 to the inner peripheral portions 14A of both ends of the roller body 14.

Also, as shown in FIG.
A groove 50 may be formed in the outer peripheral portion 16 </ b> B of the roller body 14, a heat-resistant adhesive may be put in the groove 50, and the short cylindrical body 16 may be bonded and fixed to the inner peripheral portions 14 </ b> A of both ends of the roller body 14 with the heat-resistant adhesive.

In the above embodiment, the roller body 14 is made of an aluminum alloy, but may be made of another metal such as stainless steel instead.

Next, a heating roller according to a second embodiment of the present invention is shown in FIG. 9, and this embodiment will be described with reference to FIG.

The same members as those in the first embodiment are denoted by the same reference numerals, and the description thereof will not be repeated.

As shown in FIG. 9, in the short tubular body 16 of this embodiment, a convex portion 60 for preventing heat radiation is formed in a ring shape on the inner peripheral portion of the short tubular body 16. This protrusion 60
The short cylindrical body 16 is formed in a wall shape at the longitudinally central end of the roller body 14, and a small-diameter hole 62 through which the heating element 30 can be inserted is formed at the center.

Therefore, in the present embodiment, in addition to the function and effect of the first embodiment, the high-temperature air inside the heating roller 12 is reduced by the projection 60 for preventing heat radiation formed on the inner peripheral portion of the short cylindrical body 16. Since it is difficult for the heat roller 12 to flow out, the heat retaining property of the heating roller 12 is high, and the temperature characteristics can be improved.

The position of the projection 60 for preventing heat radiation is not limited to the longitudinally central end of the roller body 14 in the short tubular body 16, but as shown in FIG.
6 may be the opposite end. The position of the protrusion 60 for preventing heat radiation is determined by the position of the roller body 1 in the short cylindrical body 16.
4 is not limited to the end on the center side in the longitudinal direction.
May be an intermediate portion in the longitudinal direction.

As shown in FIGS. 11 and 12,
The inner diameter of the short tubular body 16 may be continuously reduced along the longitudinal direction of the short tubular body 16 to form a projection 60 for preventing heat radiation.

Next, a heating roller according to a third embodiment of the present invention is shown in FIGS. 13 and 14, and this embodiment will be described with reference to these drawings.

The same members as those in the first embodiment are denoted by the same reference numerals, and duplicate description will be omitted.

As shown in FIG. 13, the short tubular body 16 of this embodiment is fixed to the outer peripheral portions 14B of both ends of the roller body 14 by press-fitting or the like as in the first embodiment.

As shown in FIG. 14, the short cylindrical body 16 fixed to the left end side of the roller body 14 has a cutout portion 64 extending along the axial direction of the short cylindrical body 16. The engaging projection 24 of the transmission gear 22 is engaged with the notch 64 and the notch 20 of the roller body 14, and the transmission gear 2
With the rotation of 2, the heating roller 12 is rotated integrally with the transmission gear 22.

Therefore, in the present embodiment, as in the first embodiment, the forming of the heating roller 12 is easy and inexpensive. Further, even if the roller body 14 is thin and lightweight, it has sufficient strength as the heating roller 12, can improve abrasion resistance and temperature characteristics, and can be a highly accurate roller.

Note that, as shown in FIG.
6, a slanted portion 16C is formed at a position on the operation surface 14F side (the right side in FIG. 15) of the roller body 14, and the short cylindrical body 1
A configuration in which the paper powder hardly accumulates at the end of 6 may be adopted. Also, as shown in FIG.
D is gradually narrowed down, and the inner peripheral portion of the short tubular body 16 is formed into an inclined surface 16D, and the outer diameter of the outer peripheral portion 16E of the short tubular body 16 is made equal to the outer diameter of the operating surface 14F of the roller body 14, and A configuration in which the paper powder hardly accumulates at the end of the cylindrical body 16 may be adopted.

[0063]

EXAMPLES (Example 1) Rollers obtained by using an aluminum strip material (5083-H material) having a thickness of 0.6 mm, performing an electric sewing process, a drawing process, and, if necessary, a PA process and a finish drawing process. Material drawing rate 20%, Finish drawing rate 5%
And tensile strength (σ _B N / mm), tensile elongation (δ%), and uneven thickness and roundness according to JIS H4080 when a roller material of 20 mmφ and (length 300 mm) was prepared. , Straightness and deflection accuracy were measured. Table 1 shows the results.

[0064]

[Table 1]

Example 2 Using a 5.0% Mg strip,
A roller material was prepared in the same manner as in Example 1 by changing the refining, plate thickness, drawing rate, and finish drawing in the states shown in Table 2, and the roller performance was measured in the same manner. Table 3 shows the results.

[0066]

[Table 2]

[0067]

[Table 3]

[0068]

As described above, the roller and the image forming apparatus for an electronic device according to the present invention have the effects of being easy to manufacture, low in cost, and having high strength and high accuracy.

[Brief description of the drawings]

FIG. 1 is an enlarged side sectional view showing an end of an electronic device roller according to a first embodiment of the present invention.

FIG. 2 is a perspective view illustrating a fixing unit of the image forming apparatus according to the first embodiment of the present disclosure.

FIG. 3 is an exploded perspective view illustrating a fixing unit of the image forming apparatus according to the first embodiment of the present disclosure.

FIG. 4 is a front view illustrating a fixing unit of the image forming apparatus according to the first embodiment of the present disclosure.

5 is a sectional view taken along line 5-5 in FIG.

FIG. 6 is an enlarged sectional side view showing an end of an electronic device roller according to a modification of the first embodiment of the present invention.

FIG. 7 is an enlarged sectional side view showing an end of an electronic device roller according to a modification of the first embodiment of the present invention.

FIG. 8 is an enlarged side sectional view showing an end of an electronic device roller according to a modification of the first embodiment of the present invention.

FIG. 9 is an enlarged side sectional view showing an end of an electronic device roller according to a second embodiment of the invention.

FIG. 10 is an enlarged sectional side view showing an end of an electronic device roller according to a modification of the second embodiment of the present invention.

FIG. 11 is an enlarged side sectional view showing an end of an electronic device roller according to a modification of the second embodiment of the present invention.

FIG. 12 is an enlarged side sectional view showing an end portion of an electronic device roller according to a modification of the second embodiment of the present invention.

FIG. 13 is an enlarged side sectional view showing an end of an electronic device roller according to a modification of the third embodiment of the present invention.

FIG. 14 is an exploded perspective view illustrating a fixing unit of an image forming apparatus according to a third embodiment of the invention.

FIG. 15 is an enlarged side sectional view showing an end of an electronic device roller according to a modification of the third embodiment of the present invention.

FIG. 16 is an enlarged sectional side view showing an end of an electronic device roller according to a modification of the third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Fixing part of image forming apparatus 12 Heating roller 14 Roller body 16 Short cylinder 34 Pressure roller 35 Conductive silicone

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) B65H 5/06 B65H 5/06 C G03G 15/20 103 G03G 15/20 103 F term (reference) 2H033 AA31 BA25 BB02 BB12 BB18 BB30 BB34 3F049 CA11 DA12 LA01 LB03 3J103 AA02 AA13 AA14 AA32 AA37 AA41 AA51 AA74 AA90 BA03 BA17 BA31 BA41 BA43 CA03 CA52 CA66 CA78 DA01 DA06 EA20 FA01 FA02 FA03 FA12 FA15 FA18 FA19 FA26 HA03 HA03 HA03 HA03 HA04 HA47 HA53 HA54 4E028 CA01

Claims (7)

[Claims] 1. An electronic device comprising: a long cylindrical roller body formed of metal; and a short cylindrical body disposed at an end of the roller body and reinforcing the end of the roller body. Roller for equipment. 2. A long cylindrical roller body which is formed of an aluminum alloy material, is heated by a heat source and is driven and rotated, and is disposed at an end of the roller body to reinforce the end of the roller body. A roller for an electronic device, comprising: a short cylindrical body; 3. The aluminum alloy material contains 4.1 to 5.6% by weight of magnesium.
3. The roller for an electronic device according to claim 2, wherein a drawing process is performed after the electric resistance sewing process. 4. The roller body has a thickness of 0.2 to 1.
The roller for electronic equipment according to claim 2 or 3, wherein the outer diameter is 0 mm and the outer diameter is 45 mmφ or less. 5. The electronic device roller according to claim 1, wherein a convex portion for preventing heat radiation is formed on an inner peripheral portion of the short tubular body. 6. An image forming apparatus, wherein the roller for an electronic device according to claim 1 is used in a fixing unit. 7. The image forming apparatus according to claim 6, wherein conductive silicone is applied to an end surface of the pressure roller pressed against the roller body.