JPH04230751A - Sheet material conveying roller and manufacture of the same - Google Patents

Abstract

PURPOSE:To provide a sheet material conveying roller simple in manufacture and high in rigidity and circularity and superior in deflection precision and to enhance dimensional stability in the wide temperature range and to reduce its weight to facilitate user maintenance. CONSTITUTION:A cylindrical resin layer 38 is formed with heating on the circumference of a preheated aluminum pipe 20, and this resin-coated pipe 20 is cut to a necessary length, and a shaft end member is coaxially fixed with each end of the pipe 20. The aluminum pipe 20 is coated with the resin layer 38 by an extrusion molding machine.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet material conveying roller used for conveying sheet material and a method for manufacturing the same.

0002

2. Description of the Related Art An automatic developing apparatus that automatically transports and processes image-exposed photosensitive materials uses a large number of transport rollers for transporting the photosensitive materials. These rollers for automatic developing devices are generally supported by a shaft that spans between two side plates, and in the case of rollers for transporting photosensitive materials, the rollers are integrally fixed to this roller. It is configured to receive the rotational force of the motor via gears and rotate while holding the photosensitive material. In addition, the rollers for automatic developing devices are designed with high runout accuracy to prevent uneven processing of photosensitive materials.
Chemical resistance, smoothness, etc. are strictly required.

[0003] In order to satisfy these demands, rollers for automatic developing devices are made by wrapping resin-impregnated paper or cloth around a metal pipe called a core metal, then cutting the pipe to a predetermined size, and attaching a metal pipe on both sides. The shaft end member for shaft support is assembled with adhesive. Here, a metal pipe, such as a stainless steel pipe, is used as the core of the roller, but when the roller is immersed in the processing liquid, the processing liquid may seep into the joint between the pipe and the shaft end member, or it may be wrapped around the roller surface. This is to prevent the core metal from corroding due to the treatment liquid permeating through the resin-impregnated paper or cloth. However, in this conventional manufacturing method, production costs are high due to the many processing steps, and the weight of the rollers is large, so if a rack incorporating many rollers is used in an automatic developing device, it will be easier to maintain the user. There were problems such as loss of performance and the need for a strong tank to house the rack.

[0004] Furthermore, a pipe-shaped modified PPO resin roller manufactured by extrusion molding without using a core pipe is known. However, such rollers are not suitable for use in sheet material conveying devices due to their rigidity, runout accuracy, and roundness. When such a roller is partially axially immersed in a liquid, such as a processing solution, the temperature difference between the liquid and the air above it causes the roller to warp.

[0005]

SUMMARY OF THE INVENTION In view of the above facts, the present invention aims to provide a roller for transporting sheet materials that is easy to manufacture and satisfies required performance characteristics such as weight reduction. do.

A further object of the present invention is to provide a method for manufacturing rollers that reduces manufacturing costs by reducing the number of processing steps.

Another object of the present invention is to provide a roller that has high rigidity, roundness, and excellent runout accuracy and is suitable for conveying sheet materials, and a method for manufacturing the same.

A further object of the present invention is to provide a roller and a roller which exhibit excellent dimensional stability even when the roller is partially immersed in a liquid such as a processing solution and which does not cause axial warping of the roller. An object of the present invention is to provide a manufacturing method thereof.

[0009]

Means for Solving the Problems In order to achieve the above object, the invention according to claim 1 provides a method for manufacturing a conveying roller used for conveying a sheet material, which comprises: a second step of applying molten resin to the outer periphery of the preheated aluminum pipe to form a resin layer; and a third step of cutting the aluminum pipe on which the resin layer has been formed in the second step into a predetermined length. and,
The present invention is characterized by comprising a fourth step of coaxially fixing shaft end members to both ends of the cut aluminum pipe.

The method for manufacturing a roller for conveying sheet material according to claim 2 is the method for manufacturing a roller for conveying sheet material according to claim 1, wherein the resin layer and the shaft end member are made of the same type of thermoplastic resin. It is characterized by

Furthermore, the method for manufacturing a roller for conveying sheet material according to claim 3 is the method for manufacturing a roller for conveying sheet material according to claim 1 or 2, further comprising the step of grinding the surface of the resin layer. It is a feature.

[0012] The cylindrical resin layer may be coated on the outer periphery of the aluminum pipe using an extrusion molding machine.

[0013] The shaft end member has a large diameter portion that is equal to or larger than the diameter of the resin layer on the outer periphery of the aluminum pipe for coaxially joining the shaft end member to the pipe, and a large diameter portion that is connected to the bearing. It has a small diameter portion used for shaft support. Further, such shaft end members are joined to both ends of the aluminum pipe by ultrasonic welding or pressure welding by friction. Further, this shaft end member is made of the same type of resin material as the resin layer covering the outer periphery of the aluminum pipe.

[0014] Furthermore, the outer peripheral surface of the aluminum pipe is
It may have an uneven shape. Preheat the aluminum pipe to a temperature of about 150°C to about 230°C, and heat it to about 160°C.
A cylindrical resin layer is formed on the outer periphery of the aluminum pipe at a temperature in the range of 230°C to 230°C.

[0015] After the shaft end members are joined to both ends of the aluminum pipe which has been cut to a required length and coated with resin, the surface of the resin layer may be finished by grinding.

A sheet material conveying roller according to a fourth aspect of the present invention includes an aluminum pipe having a thermoplastic resin layer on its outer surface, and shaft end members coaxially joined to both ends of the pipe.

[0017] In the sheet material conveying roller according to claim 5, an aluminum pipe is preheated, a cylindrical resin layer is formed on the outer periphery of the aluminum pipe while heating, and a cylindrical resin layer is formed on the outer periphery. It is constructed by cutting an aluminum pipe to a predetermined length, and coaxially fixing shaft end members to both ends of the cut aluminum pipe.

A sheet material conveying roller according to a sixth aspect of the present invention is characterized in that it is manufactured by the method of manufacturing a sheet material conveying roller according to the third aspect.

The radial thickness of the aluminum pipe is 0.
．． 5 to 5.0 mm, and the radial thickness of the resin layer may be in the range of 0.3 to 3.0 mm.

[0020] Polyvinyl chloride may be used as the resin material for the thermoplastic resin layer. In order to increase the adhesive force with the thermoplastic resin, the outer surface of the aluminum pipe may be formed with an uneven shape.

[0021] Furthermore, an adhesive may be interposed between the outer surface of the aluminum pipe and the resin.

[0022] The thermoplastic resin of the same type as described in claim 2 refers to a shaft end member made of resin that is joined to the resin layer covering the aluminum pipe and both ends of the aluminum pipe by ultrasonic welding or welding by pressure contact friction. Refers to the resin used for the resin layer and shaft end member that are sufficiently bonded to the shaft end member.

[0023]

[Operation] In the sheet material conveying roller and the manufacturing method thereof according to the present invention, after preheating an aluminum pipe, molten resin is applied to the outer periphery of the aluminum pipe to form a resin layer, and the aluminum pipe is stretched to a predetermined length. Since the shaft end members are coaxially fixed to both ends of the cut aluminum pipe, it is possible to reduce processing steps and reduce costs, and the roller core is made of a corrosion-resistant metal material such as stainless steel. Since lightweight aluminum is used instead of aluminum, weight can be reduced.

Furthermore, since the resin layer on the outer periphery of the aluminum pipe and the shaft end members joined by welding to both ends of the aluminum pipe are made of the same type of resin, the resin layer and the shaft end members are joined without any gaps, and the roller Since the entire aluminum pipe, which is the core metal, is covered with thermoplastic resin, even if the roller is immersed in the processing liquid, the processing liquid will not penetrate inside the roller, and the aluminum pipe will not be corroded by the processing liquid.

Therefore, the sheet material conveying roller of the present invention is composed of an aluminum pipe having a thermoplastic resin layer on the outer surface and shaft end members coaxially joined to both ends of the pipe. , exhibits excellent dimensional stability even when the roller is partially immersed in a liquid such as a processing solution, and does not cause axial warping of the roller.

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 2 shows a roller 10 to which the present invention is applied, which is used in an automatic developing apparatus for processing photosensitive materials such as seed materials such as X-ray films and printing films. This roller 10 is an aluminum pipe 20
A resin layer 38 is coated on the outer periphery with a predetermined thickness.

[0027] The aluminum pipe 20 is a hollow pipe, for example, about 1.0 to 10.0 m (preferably 2 m long).
．． 0 to 5.0 m) and approximately 0.5 to 5 m
It has a predetermined thickness of m (preferably about 1 to 2 mm) and has extremely precise roundness and runout accuracy.

The thickness of the resin layer 38 is approximately 0.3 to 3.0 m.
m, preferably about 1.0 to 2.0 mm. For example, an aluminum pipe with a length of 3.0 m, a thickness of 1.5 mm, and an outer diameter of 22 mm is made of hard polyvinyl chloride resin (for example, Vinica Compound T-20 BK3 manufactured by Mitsubishi Kasei Vinyl Co., Ltd.) with a thickness of 1.6 mm. ) coated with a layer of The tolerance range for the resin layer thickness is about 0+0.05 mm.

As the resin material 32 of the resin layer 38, relatively inexpensive hard polyvinyl chloride resin, noryl resin, etc. can be used, and although other materials are also applicable, thermoplastic resin is preferable.

A shaft end member 36 is fixed to both open ends of the aluminum pipe 20 and the resin layer 38 in the axial direction. This shaft end member 36 is preferably made of the same type of resin as the resin layer 38, and includes a large diameter portion 36A and a small diameter portion 36B. The large diameter portion 36A has the same diameter as the outer diameter of the resin layer 38, and the small diameter portion 36B is formed coaxially with the large diameter portion 36A, and is used for supporting a bearing (not shown). Next, a manufacturing procedure for the roller 10 configured as described above will be explained.

As shown in FIG. 1A, the aluminum pipe 20 is arranged so that its axis is perpendicular to the axis of the heating cylinder 28 of the extrusion molding machine 22. As shown in FIG. aluminum pipe 2
0, the aluminum pipe 20 is heated from about 150°C to 23°C by a feeding device for the aluminum pipe 20 (not shown).
It is fed to a preheating zone 21 which is preheated by heating means 23 to 0°C, preferably in the range from about 190°C to 215°C. The heating means 23 is an electric heater, a high frequency generator, or the like. The high frequency generator generates a high frequency of about 300,000 Hz. By preheating the aluminum pipe 20, solidification of the resin material 32 within the die 24 or cracking of the resin layer 38 can be prevented. Next, the aluminum pipe 20 is conveyed to a passage within the die 24 provided in the heating cylinder 28. This size is such that the resin-coated aluminum pipe 20 can pass through it. The dice 24 are heated to approximately 16 mm by heating means (not shown).
Since the resin material 32 is heated in a range of 0°C to about 230°C, preferably about 195°C to 215°C, the resin material 32 does not solidify. The supplied aluminum pipe 20 is moved in a horizontal direction (in the direction of arrow A) perpendicular to the axis of the heating cylinder 28 of the extruder 22 while being extruded by the pipe extruder 64 .

In the extrusion molding machine 22 , the resin material 32 introduced from the hopper 26 is heated and softened in the heating cylinder 28 . This heated and softened resin material 32 is pressurized by a screw 30 driven by a motor 33 and extruded from the tip of the heating cylinder 28 to the die 24 . Within the heating cylinder 28, the temperature gradient from the hopper 26 to the tip of the heating cylinder 28 is approximately 1
65°C to 190°C. In this way, the resin layer 38 is formed around the outer periphery of the aluminum pipe 20.

A positioning device 60 is provided near the die 24 to adjust the position of the aluminum pipe 20 and the die 24. This positioning device 60 is provided with adjusting rollers 62, which adjust the position of the aluminum pipe 20 so that the distance between the outer circumference of the aluminum pipe 20 and the inner circumferential surface of the die 24 is maintained constant. Adjust and hold the insertion angle to the die 24, and
Alternatively, as shown in FIG. 1B, a resin layer 38 having a uniform thickness is formed around the outer periphery of the aluminum pipe 20.

This positioning device 60 can be finely adjusted vertically or horizontally with respect to the extrusion direction (direction of arrow A) of the aluminum pipe 20, thereby aligning the axis of the aluminum pipe 20 with the axis of the die 24. The structure is as follows. The die 24 is formed with a circular hole 24A through which the aluminum pipe 20 passes. A molded circular groove 24B is formed by enlarging the inner diameter of this circular hole 24A, and serves as a filling portion for the molten resin passing through the heating cylinder 28. This molding circular groove 24B is formed in the die 24 in FIG. 1A.
formed on the right side. Therefore, the aluminum pipe 20 passing through the die 24 is molded around the outer periphery of the filled molten resin. A general molding machine used for extrusion molding of resin can be applied to this extrusion molding machine 22.

Since the aluminum pipe 20 coated with the resin layer 38 is slowly cooled by air flow and water mist (not shown), cracks in the resin layer 38 do not occur.

Next, as shown in FIG. 2, at both ends 34 of the aluminum pipe 20, which has been cut to the required length and coated with resin, a shaft with a core made of the same type of resin as the coated resin is attached. The end members 36 are joined by ultrasonic welding or pressure friction welding.

Next, the surface of the resin layer 38 is finished by grinding. Although not shown, in order to improve the smoothness of the coated surface of the aluminum pipe 20, the coated surface is ground by dry honing or the like. Another method of grinding is cylindrical grinding, but in that case, it is desirable to use a grindstone with wide abrasive grain spacing and low bonding, and to use a grinding fluid to reduce the heat generated by grinding and prevent clogging. Note that this grinding step can be omitted if there is no need.

Next, FIG. 3 shows a second embodiment of the present invention. Instead of the regular length aluminum pipe 20, an aluminum ingot 40 is extruded using an extruder 44, and the aluminum pipe 20 is continuously supplied. As shown in FIG. 3, the extruder 44 includes a container 46 containing the aluminum ingot 40, a ram 48 that applies strong pressure to the aluminum ingot 40, and extrudes the ingot 40 in the direction of arrow A to form the aluminum pipe 20. Dice 50 with slit 50A
It consists of

The aluminum pipe 20 that is continuously extruded in this way is placed perpendicular to the axis of the heating cylinder 28 of the extrusion molding machine 22, and after being preheated in the preheating area 21 similar to the above embodiment, this extrusion molding is performed. The machine 22 coats the outer periphery of the aluminum pipe 20 with a resin layer 38 . The aluminum pipe 20 coated with the resin layer 38 is slowly cooled as described in the previous embodiment. Note that this extrusion molding machine 22 has the same structure as that of the previous embodiment.

The aluminum pipe 20 coated with the resin layer 38 is further sent in the direction of arrow A to a cutting machine 4 equipped with a circular saw or the like that moves at the same speed as the aluminum pipe 20.
Step 2: Cut to the required length. Thereafter, cored shaft end members 36 are fixed to both ends of the aluminum pipe 20 in the axial direction,
The point that the outer periphery of the resin pipe 54 is ground is the same as in the previous embodiment.

FIG. 4 shows a third embodiment of the invention. In this embodiment, unlike the previous embodiment, the outer periphery of an aluminum pipe 20 is not coated with resin using an extrusion molding machine 22, but a resin pipe 5 is formed in advance into a cylindrical shape.
4 is press-fitted into the outer periphery of the aluminum pipe 20. This press-fitting operation is preferably performed after the resin pipe 54 is heated and softened. If necessary, both ends of the aluminum pipe 20 and the resin pipe 54 may be cut or the outer periphery of the resin pipe 54 may be ground after press-fitting. Further, the shaft end members 36 with shaft cores are fixed to both ends of the aluminum pipe 20 in the axial direction, and the outer periphery of the resin pipe 54 is ground, as in the previous embodiment.

FIG. 5 shows a fourth embodiment of the invention. In this embodiment, minute irregularities 58 whose longitudinal direction is parallel to the axial direction of the aluminum pipe 20 are formed in advance on the outer circumferential surface 56 of the aluminum pipe 20. As a result, the inner circumferential surface of the resin layer 38 enters the concave portion of the uneven shape 58, and the aluminum pipe 20
This increases the degree of adhesion of the resin layer 38. Therefore, when the photosensitive material is pinched and conveyed by the pair of rollers manufactured in this manner, the outer circumferential surface 56 of the aluminum pipe 20 and the inner circumferential surface of the coated resin layer 38 are not inadvertently misaligned around the axis. . Other manufacturing methods and configurations are the same as in each of the above embodiments.

In addition to such an uneven shape 58, the outer circumferential surface 56 of the aluminum pipe 20 and the resin layer 38 covered therewith are
Various uneven shapes such as knurling or numerous pin-like protrusions can be applied to strengthen the bond with the material.

[0044]Also, the aluminum pipe 20 can be formed by interposing an adhesive between the outer circumferential surface 56 of the aluminum pipe 20 and the resin layer 38 without providing the uneven shape, or by using an adhesive in combination with the uneven shape. Outer peripheral surface 56 and resin layer 38
It is possible to strengthen the bond with

Although the sheet material conveying roller according to the present invention can be used in an automatic developing device for processing photosensitive materials such as X-ray film and printing film, it is not limited to this and can be used in various applications. It can be used for various purposes. .

[0046]

[Effects of the Invention] Since the sheet material conveying roller according to the present invention is manufactured as explained above, it is possible to reduce processing steps, reduce costs, and reduce the weight of the roller. By reducing the weight, it is possible to reduce the weight of the device incorporating the rollers, simplify user maintenance, and improve the strength and safety of the tank that accommodates the rack equipped with the rollers. Further, the sheet material conveying roller according to the present invention has excellent rigidity, roundness, runout accuracy, and dimensional stability over a wide temperature range.

[Brief explanation of the drawing]

FIG. 1(A) is a plan view showing a step of coating an aluminum pipe with resin according to a first embodiment of the present invention. (B) is a sectional view of the extrusion molding machine of the present invention.

FIG. 2 is a side cross-sectional view of a roller manufactured according to the invention.

FIG. 3 is a plan view of a second embodiment of the present invention showing the process of continuously supplying aluminum pipes.

FIG. 4 is a cross-sectional view of a third embodiment showing a step of press-fitting a resin pipe onto the outer periphery of an aluminum pipe.

FIG. 5 is a partially cutaway perspective view of a fourth embodiment showing an aluminum pipe having an uneven surface.

[Explanation of symbols]

20 Aluminum pipe 21 Preheating area 22 Extrusion molding machine 36 Shaft end member 38 Resin layer 54 Resin pipe

Claims (6)

[Claims] 1. A method for manufacturing a conveying roller used for conveying sheet material, comprising a first step of preheating an aluminum pipe, and applying molten resin to the outer periphery of the preheated aluminum pipe. a second step of forming a resin layer; a third step of cutting the aluminum pipe on which the resin layer has been formed in the second step into a predetermined length; and coaxially fixing shaft end members to both ends of the cut aluminum pipe. A method for manufacturing a sheet material conveying roller, comprising a fourth step. 2. The method for manufacturing a sheet material conveying roller according to claim 1, wherein the resin layer and the shaft end member are made of the same type of thermoplastic resin. 3. The method of manufacturing a roller for conveying a sheet material according to claim 1 or 2, further comprising the step of grinding the surface of the resin layer. 4. A sheet material conveying roller comprising an aluminum pipe having a thermoplastic resin layer on its outer surface, and shaft end members coaxially joined to both ends of the pipe. 5. A roller for conveying a sheet material, characterized in that it is manufactured by the method for manufacturing a roller for conveying a sheet material according to claim 1 or 2. 6. A sheet material conveying roller manufactured by the method for manufacturing a sheet material conveying roller according to claim 3.