JPH11125984A - Production of roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to stably mold a roller with high accuracy without variation in its thickness by disposing an elastic member provided with plural grooves on the contact surface side with a metal mold of a hot plate for heating. SOLUTION: A cap cover 30 provided with a liquid introducing hole 30A communicating with the outside is fitted to the outer side of a cap 20 on the left side and the metal mold 10 is screwed and fixed thereto. A cap cover 32 preventing the leakage of the elastic material is fitted to the outer side of the cap 22 on the right side and is screwed and fixed to the metal mold 10. In such a case, the elastic material is introduced into a mold cavity and is put in the hot plate 40 for heating divided in parallel with the axial direction of the metal mold, to heat the elastic material. The rubber thickness on the deepest side of the elastic member 41 is, for example, 2 mm and the rubber thickness of the part nearest the parting plane is, for example, 1 mm. Further, the groove width of the elastic member 41 is, for example, 1 mm and the intervals of the grooves is, for example, 10 mm and the depth is, for example, 1 mm in the part on the deepest side and is gradually smaller toward the parting plane. The elastic member 41 is stuck by an adhesive to the surface of the hot plate 40 in contact with the metal mold.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as an electrophotographic apparatus or an electrostatic recording apparatus, which is suitable for a fixing device for fixing unfixed toner. The present invention relates to a method of manufacturing a roller for forming an elastic material into a cylindrical shape integrally with the cored member.

[0002]

2. Description of the Related Art Conventionally, in a molding die having a penetrated cylindrical hole, a metal mold having a lid at both openings of the cylindrical hole for holding a shaft-shaped core metal member concentrically with the cylindrical hole. Using a mold, heat it by sandwiching it with a heating platen for heating divided in parallel to the axial direction of the cylindrical molding die, or make a hole in the heating plate so that the cylindrical molding die enters. Rollers have been manufactured by inserting a molding die into the hole and heating the same to form an elastic material cylindrically and integrally with the core metal member around the shaft-shaped core metal member. The heating hot plate has been made of a metal material because the mold contact surface has good strength and good thermal conductivity.

[0003] However, if the cylindrical molding die is sandwiched by such a hot platen, even if the shape of the contact surface of the hot plate is adjusted to the external shape of the cylindrical molding die, the contact portion is inevitably formed due to its structure. It becomes linear. Also, when a molding die is inserted into the hole of the hot plate, the contact portion becomes linear or dotted. In other words, the efficiency of heat transfer is reduced, and there is a difference in how the temperature of the molding die rises between the contact portion and the non-contact portion.

[0004] When the thickness of the elastic layer of the roller is sufficient, there is no problem in a slight rise in the temperature of the molding die, but when the thickness is very small, or when the elastic layer is further formed on the elastic layer. In some cases, there is a problem that the difference in the temperature rise of the molding die has a large effect, and the difference in the curing time causes a variation in the thickness of the elastic layer, which results in roller runout. Therefore, when the thickness of the elastic layer of the roller is small, or when the elastic layer is further molded on the elastic layer, there has been a demand for the development of a molding method in which the thickness of the elastic layer does not vary.

[0005]

As described above, in the conventional example, there is a difference in how the temperature of the molding die rises between the contact portion and the non-contact portion between the heating plate and the molding die, and the elastic layer of the roller is hardened. When the thickness is thin, or when the elastic layer is further molded on the elastic layer, the effect of the difference in temperature rise of the molding die is greatly expressed, and the thickness of the elastic layer varies due to the difference in the curing time. However, such a phenomenon occurs as roller runout, and molding of a high-precision thin-walled roller and a multi-layer roller using a heating plate has a large product variation, and it has been difficult to stably manufacture the roller.

An object of the present invention is to provide a roller having a thin elastic layer as described above or a multi-layer roller in which an elastic layer is further formed on an elastic layer without causing any variation in wall thickness. An object of the present invention is to provide a method of manufacturing a roller using a heating plate capable of being formed with high precision in a mold heating method.

[0007]

The above objects and objects are solved and achieved by the present invention described below. That is, the present invention provides a molding die having a lid attached to both ends of the cylindrical hole for holding a shaft-shaped core metal member concentrically with the cylindrical hole in a molding die having a penetrated cylindrical hole. Using a mold, an elastic material is introduced into the molding die by press-fitting or evacuation, and heated by a heating platen which is divided in parallel in the axial direction of the cylindrical molding die. In a method of manufacturing a roller in which an elastic material is formed cylindrically and integrally with a core metal member around a metal member, an elastic material having a plurality of grooves provided on a contact surface side of the heating hot plate with a molding die is provided. A method for manufacturing a roller, which includes disposing members, is disclosed.

In the method of manufacturing a roller according to the present invention, the thickness of the elastic member on the hot platen may be such that “the vicinity of the split surface <the back side” on the cut surface perpendicular to the axial direction of the mold of the split hot plate. Or the elastic member is a silicone rubber, or the elastic member is a fluoro rubber. It is.

(Function) In order to achieve the above object, a first invention according to the present application is to hold a shaft-shaped core metal member concentrically with a cylindrical hole in a molding die having a penetrated cylindrical hole. A molding die having a lid attached to both ends of the cylindrical hole is used, and an elastic material is introduced into the molding die by press-fitting or evacuation, and is divided in parallel to the axial direction of the cylindrical molding die for heating. Heated by a hot plate, around the shaft-shaped core metal member,
In the molding of the roller, which is formed by molding an elastic material into a cylindrical shape integrally with the core metal member, it is preferable to dispose an elastic member having a plurality of grooves on a contact surface of the heating hot plate with a molding die. Features.

[0010] By disposing an elastic member on the contact surface of the heating platen with the molding die, the contact portion, which had previously been metal-to-metal and was inevitably linear or dot-shaped in its structure, The elastic member absorbs both irregularities, and can be brought into contact with the entire side surface of the molding die. In addition, by providing a plurality of grooves in the elastic member, air pockets generated at the interface between the heating platen and the molding die can be eliminated, and the adhesion between the heating platen and the molding die can be improved.

Thus, the problem that the difference in temperature rise of the molding die between the contact portion and the non-contact portion becomes large can be solved, and even if the roller has a thin elastic layer, Further, even with a multi-layer roller for forming an elastic layer, it can be formed stably with no thickness variation and with high precision.

A second invention according to the present application relates to an elastic member disposed on a contact surface of a heating platen for heating divided in parallel to an axial direction of a cylindrical molding die, and having a thickness of each divided member. On a hot platen, on a cut surface perpendicular to the axial direction of the mold,
The relationship is such that “near the division plane <rear side”.

[0013] By doing so, it is possible to reduce the large frictional resistance that occurs when the elastic member is arranged on the heating plate with a uniform thickness, so that high adhesion to the molding die can be realized even at a lower pressing pressure. Can be. Therefore, from the vicinity of the split surface of the heating hot plate to the back side, it is possible to make uniform contact at a lower pressure evenly, and it is not necessary to perform press molding at a high pressure, thereby eliminating the adverse effects such as deformation of the mold and deterioration of the roller shape. be able to.

A third invention according to the present application is characterized in that the elastic member is a silicone rubber. The requirement for an elastic material is that it needs to have excellent heat resistance and good heat conduction for use in a heating plate.

As described above, by using silicone rubber as the elastic member, the elasticity is maintained without deterioration even at a heating temperature of a few hundred degrees (° C.), and the thickness of the elastic layer is brought into contact with the entire side surface of the molding die. A roller having a small thickness or a multi-layer roller in which an elastic layer is further formed on an elastic layer can be formed stably with no thickness variation and using a heating plate in a mold heating method with high precision. Furthermore, since the hardness is more easily reduced than urethane rubber, the thickness as an elastic member can be reduced. That is, the heat conduction efficiency is improved, the molding time can be shortened, or the molding temperature can be lowered, and the durability can be further improved.

A fourth invention according to the present application is characterized in that the elastic member is made of fluoro rubber. The requirement for the elastic material is that it has excellent heat resistance and good heat conduction for use in a heating plate.

Further, by using a fluorine rubber which is superior in heat resistance and strength to the silicone rubber, it is possible to achieve a temperature of several hundred degrees (° C.).
Keeps its elasticity without deterioration even under the heating temperature of
It does not break even when the mold is repeatedly inserted and removed, and even if the roller has a thin elastic layer by contacting the entire surface of the mold, or a multilayer roller that forms an elastic layer on the elastic layer, it is stable. There is no thickness variation, and the heating plate can be formed with high precision using a mold heating method.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described below with reference to the drawings based on embodiments, but the present invention is not limited to these embodiments.

[Embodiment 1] FIG. 1 is a drawing which best illustrates the features of the present invention. FIG. 1 (a) is an external perspective view showing a state of an elastic roller being molded by the apparatus of the present embodiment, and FIG. It is sectional drawing (b). In FIG. 1, reference numeral 10 denotes a molding die having a cylindrical hole 12 therethrough. The cylindrical hole 12 is subjected to a honing finish to secure the accuracy of the outer surface of the elastic roller after molding. Lids 20 and 22 are fitted to the openings 16 and 18 at both ends of the cylindrical hole 12.
The core member 26 is held concentrically with the inner surface of the cylindrical hole 12 by being fitted into the holes 20B and 22B on the central axis of the lid.

A cover 30 provided with a liquid introduction hole 30A communicating with the outside is fitted on the outside of the left cover 20, and is fixed to the molding die 10 by screws. Right lid 2
A lid cover 32 for preventing leakage of the elastic material is fitted on the outer side of 2, and is screwed to the molding die 10.

FIG. 1 shows a state in which the elastic material has already been introduced into the mold cavity, and is put into a heating platen 40 for heating which is divided in parallel to the axial direction of the mold. It is in a state of being heated.

FIG. 2 is a cross-sectional view of the elastic member 41 taken along the line AA perpendicular to the axial direction of the mold. The rubber thickness at the innermost part is 2 mm, and the rubber thickness at the part closest to the dividing plane is 1 mm.
It is. The width of the groove of the elastic member is 1 mm, the interval between the grooves is 10 mm, and the depth is 1 mm at the deepest part on the deeper side, and becomes smaller as approaching the division surface. Hot plate 4
At 0, an elastic member 41 is attached to the contact surface with the molding die with an adhesive.

Next, the procedure of forming an elastic roller using the apparatus of the present embodiment as described above will be described. In this embodiment, an LTV (low-temperature curing type) silicone rubber roller having a thickness of 1 mm was molded.

First, the left end portion 26A of the cored bar member 26 to which an adhesive has been applied beforehand is inserted into the support portion 20B. Next, the assembly assembled as described above is inserted into the cylindrical hole 12 of the molding die 10 from the right. The insertion is performed until the lid 20 comes into close contact with the end face of the opening 16 of the cylindrical hole 12.

Thereafter, another cover 22 is fitted into the right opening of the cylindrical hole 12. At this time, the end 26B of the metal core member 26 is inserted into the hole of the support portion 20A of the lid 22. Thus, the cylindrical hole 12 becomes a closed space. Further, the lid cover 32 is fitted to the right side of the right lid 22 of the object assembled as described above, and the lid cover 30 is fitted to the left side of the left lid 20, and is fixed to the molding die 10 with screws. I do.

In this state, the lid 30 is inserted into the closed space.
A low-viscosity rubber material, for example, LTV silicon rubber, is injected under pressure from the inlet 30A provided in the cover 20 through the liquid passage of the lid 20. At this time, the LTV rubber is degassed by stirring until the liquid is sufficiently mixed before the injection. The introduced liquid pressure was 50 kgf / cm ² . The mold is placed on a hot plate 40 on which a 1 mm-thick urethane rubber sheet is adhered with an adhesive as an elastic member 41 on the contact surface with the molding die, and is heated and cured. First, the heating platen 40 for heating divided in parallel to the axial direction of the molding die is opened, and the above-mentioned mold is put therein. In this state, the heating platen 40 is closed and the elastic member 41 is heated while being pressed. Here, after the liquid is introduced, it is also possible to assemble a mold placed in a hot platen and to introduce the liquid in a state of being heated by the hot platen 40. In this embodiment, 12
Heat at 0 ° C. for 30 minutes.

After the rubber is cured, the molding die 10 is taken out of the hot platen, and the lids and lid covers at both ends are integrally removed from the molding die 10. Finally, the roller is extracted from the molding die 10 in the axial direction to obtain an elastic roller.

By using such a hot plate and forming by the above method, a thin roller having a thickness of 1 mm or less could be formed stably with no thickness variation and with high precision. In addition, similarly, a roller having a thickness of 2 mm is put in place of the core metal,
The two-layer roller, which forms a silicone rubber having a thickness of about 1 mm on its surface, can also be formed with high accuracy by using such a hot plate and by performing the above-mentioned method stably without thickness variation. Was. The elastic material can be introduced by vacuuming instead of the press-fitting method.

[Embodiment 2] In this embodiment, the elastic member 41 is used.
In this case, silicone rubber was used in place of the urethane rubber used in Example 1. In this embodiment, an LT having a thickness of 1 mm is used.
A V silicone rubber roller was molded. The procedure for forming the elastic roller using the apparatus of this embodiment is the same as that of the first embodiment.

By using silicone rubber having a hardness lower than that of urethane rubber, the thickness of the elastic member 41 can be reduced to 1 mm on the far side where the rubber thickness is the largest, so that the efficiency of heat conduction increases and the molding time is reduced to 120 ° C. From 30 minutes, 12
The time could be reduced to 20 minutes at 0 ° C. At this time, the rubber thickness on the innermost side of the elastic member 41 is 1 mm, and the rubber thickness on the portion closest to the division surface is 0.5 mm. The width of the groove of the elastic member is 1 mm, the interval between the grooves is 10 mm, and the depth is 0.5 mm at the deepest part on the deeper side, and becomes smaller as approaching the division surface. An elastic member 41 is attached to the hot platen 40 with an adhesive on a contact surface with a molding die.

Further, since silicone rubber has a higher heat-resistant temperature than urethane rubber, there is no problem such as chipping or peeling due to rubber deterioration even when the number of moldings is increased without deterioration during heating. By using a heating plate using silicone rubber instead of urethane rubber as the elastic member 41 as described above, a thin roller having a thickness of 1 mm or less can be formed stably with no thickness variation and with high precision. did it. Further, the durability of the elastic member itself was improved, and problems such as chipping and peeling due to rubber deterioration did not occur. Further, similarly, a roller having a thickness of 2 mm is inserted instead of the core metal,
The two-layer roller, which forms a silicone rubber having a thickness of about 1 mm on its surface, can also be formed with high accuracy by using such a hot plate and by performing the above-mentioned method stably without thickness variation. Was.

[Embodiment 3] In this embodiment, the elastic member 41 is used.
As a result, fluorine rubber was used in place of the urethane rubber used in Example 1. In this embodiment, the LTV having a thickness of 1 mm is used.
A silicone rubber roller was molded. The procedure for forming the elastic roller using the apparatus of this embodiment is the same as that of the first embodiment. Fluororubber has a higher heat resistance temperature than silicone rubber or urethane rubber, so there is no deterioration during heating and the strength of the rubber itself is better than silicone rubber. The problems such as chipping and peeling due to the occurrence of the problem no longer occur. For this reason, when the thickness of the elastic member 41 is 2 mm, the molding temperature is 120 ° C.
To 140 ° C and the molding time is 3
The time was reduced from 0 minutes to 15 minutes.

By using a heating plate using fluorine rubber instead of urethane rubber as the elastic member 41 as described above, a thin roller having a thickness of 1 mm or less can be stably formed with high accuracy without thickness variation. It could be molded. Further, the strength and durability of the elastic member itself were improved, and problems such as chipping and peeling due to scratches and rubber deterioration did not occur. Further, similarly, a roller having a thickness of 2 mm is inserted instead of the core metal,
The two-layer roller, which forms a silicone rubber having a thickness of about 1 mm on its surface, can also be formed with high accuracy by using such a hot plate and by performing the above-mentioned method stably without thickness variation. Was.

[Comparative Example 1] In this comparative example, the same urethane rubber as that of Example 1 was used as the elastic member 41, but the rubber thickness on the innermost side was 2 mm, and the rubber thickness on the part closest to the dividing plane was also the same. 2 mm. And the width of the groove of the elastic member is 1
mm, the interval between grooves was 10 mm, and the depth was uniformly 1 mm.

An elastic member 41 is attached to the hot platen 40 with an adhesive on a contact surface with a molding die. In this comparative example, 1
The LTV silicone rubber roller having a thickness of mm is molded, and the procedure of molding the elastic roller is the same as that of the first embodiment.

In this comparative example, the molding die came into contact with the heating plate in the vicinity of the divided surface of the heating plate and received resistance, so that the heating plate could not fully close and the molding die could not adhere to the heating plate. Therefore, the molding time required 50 minutes. Also, roller runout,
Shape accuracy such as thickness variation also deteriorated.

[0038]

As described above, the heating plate of the present invention can be applied to a roller having a thin elastic layer or a multilayer roller in which a thinner elastic layer is formed on the elastic layer. When used in the mold heating method, even if the pressing pressure of the heating plate is lowered, the molding die and the heating plate do not generate air pockets, etc.
Adhesion can be made evenly, there is no thickness variation, and molding can be performed with high precision.

In addition, by selecting an elastic material, it is possible to obtain a temperature
It has a remarkable effect of maintaining good elasticity without deterioration even at the heating temperature, not being destroyed by repeated insertion and removal of the mold, making contact with the entire side surface of the molding die, and being able to manufacture rollers stably. Play.

[Brief description of the drawings]

FIG. 1 is a schematic explanatory view showing a roller manufacturing method of the present invention.
(However, (a) is a configuration diagram, (b) is a cross-sectional view)

FIG. 2 is a schematic explanatory view showing a hot plate according to the present invention. (However, (a) is a configuration diagram, (b) is a cross-sectional view)

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Molding die 12 Cylindrical hole 16,18 Opening 20,22 Lid 26 Core metal member 30A Introducing hole 30,32 Lid cover 40 Hot plate 41 Elastic member 42 Perforated hot plate

Continued on the front page (72) Inventor Osamu Satsuki Canon Inc. 3- 30-2 Shimomaruko, Ota-ku, Tokyo

Claims (4)

[Claims] 1. A molding die having a cylindrical hole therethrough,
Using a molding die having lids attached to both ends of the cylindrical hole for holding a shaft-shaped core metal member concentrically with the cylindrical hole, an elastic material is press-fitted or evacuated to the molding die. Introduced and heated by a heating hot plate divided in parallel to the axial direction of the cylindrical molding die, and an elastic material is cylindrically integrated with the cored metal around the shafted cored member. A method for manufacturing a roller, comprising: forming an elastic member having a plurality of grooves on a contact surface of a heating platen with a molding die; 2. The method according to claim 1, wherein the thickness of the elastic member on the hot platen has a relationship of “near the split surface <rear side” on a cut surface perpendicular to the axial direction of a mold of the split hot plate. The method for manufacturing a roller according to claim 1. 3. The method according to claim 1, wherein the elastic member is a silicone rubber. 4. The method according to claim 1, wherein the elastic member is made of fluoro rubber.