JP3402955B2 - Method for manufacturing roller having double layer structure - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a roller having a two-layer structure which is used as a feed roller for an automatic photo developing machine.

[0002]

2. Description of the Related Art A photographic automatic developing machine draws out a roll of photographic paper, exposes it, and then conveys it with rollers to continuously develop a developing solution, a stop solution, a fixing solution, and a washing solution. It is designed to pass through water for drying. This roller needs to have a strict straightness in order to convey the printing paper straight, and also needs to have a surface made of a flexible material having high smoothness so as not to damage the printing paper. Therefore, in the past, a cylindrical metal rod such as steel or stainless steel, which is easy to obtain straightness, coated with a soft synthetic resin was used. However, since a large number of rollers are used in the automatic processor, the use of a metal rod for these rollers has a drawback that the weight of the apparatus becomes too heavy.

Therefore, as shown in FIG. 6, instead of the metal rod, a hard synthetic resin is molded into a cylindrical shape to form an inner layer portion 2.
Conventionally, a roller 1 in which the outer layer portion 3 made of soft synthetic resin is coated on the roller 1 has been proposed. The roller 1 having such a two-layer structure can be easily extrusion-molded integrally by a two-layer simultaneous extrusion molding method.

[0004]

However, a conventional two-layer structure roller extruded by the two-layer simultaneous extrusion molding method has an interface between the inner layer portion 2 and the outer layer portion 3 due to a difference in heat shrinkage ratio during cooling and solidification. May peel off, and the inner layer portion 2 and the outer layer portion 3
There is a problem that idling may occur between the outer layer 3 and the outer layer 3 and the outer layer portion 3 may be displaced in the axial direction.

This problem is not limited to extrusion molding by the two-layer simultaneous extrusion molding method, but can also occur in the case of a two-layer structure roller made of synthetic resin by another manufacturing method. Further, this problem is not limited to the roller for feeding the printing paper used in the automatic developing machine, and is the same in the case of the two-layered synthetic resin roller used for other purposes.

The present invention has been made in view of such circumstances, and by providing a spiral groove on the peripheral side surface of the inner layer portion, even if peeling occurs at the interface between the inner layer portion and the outer layer portion, idling occurs. It is an object of the present invention to provide a method for manufacturing a roller having a two-layer structure that does not cause misalignment.

[0007]

That is, in order to solve the above-mentioned problems, in the method for manufacturing a roller having a two-layer structure according to claim 1 of the present invention, a thermoplastic hard synthetic resin is extruded to form a peripheral surface. A cylindrical inner layer portion having a plurality of grooves is formed on the inner surface of the inner layer portion, and the outer layer portion is formed by coating the outer periphery of the inner layer portion with another thermoplastic synthetic resin, thereby extruding a two-layer synthetic resin rod. A two-layer simultaneous extrusion molding step and a long-land die step of cooling by inserting a two-layer structure synthetic resin rod extruded by this two-layer simultaneous extrusion molding step into a long long-range die with a predetermined inner diameter. And a rotation applying step of applying a torque about the shaft center to give a twist to the synthetic resin rod having a two-layer structure solidified by cooling in the long-land die step, and a two-layer structure having a twist added in the rotation applying step. Synthetic resin rod Characterized in that a roller cutting step of the roller is cut into those lengths.

According to the means of claim 1, since the groove is formed in the inner layer portion by the two-layer simultaneous extrusion molding step and the twist is applied in the rotation imparting step, the groove of the inner layer portion is made substantially spiral. You can In addition, when a torque is applied in the rotation imparting step, the synthetic resin rod having a two-layer structure in the midst of solidification in the long Rongland die is twisted, so that the synthetic resin rod is twisted and bent, or the outer diameter is uneven. It will not solidify in a normal state. Moreover, since the two-layer synthetic resin rod sequentially rotates in the long long die, the cooling in the circumferential direction is made uniform and the straightness can be improved. The synthetic resin rod having a two-layer structure that is solidified by being twisted in this way becomes a roller having a predetermined width by being cut into an appropriate length in the roller cutting step.

Further, in the rotation imparting step according to the second aspect of the present invention, oil is filled around the synthetic resin rod having a two-layer structure solidified in the long ground die step, and this oil is rotated around the synthetic resin. It is characterized in that torque is applied by doing so.

According to the above-mentioned means, since the oil is rotated around the solidified two-layer structure synthetic resin rod, torque is applied to the synthetic resin rod by hydrocoupling due to the viscosity of the oil. be able to. Moreover, since the torque is not directly applied by sandwiching the outer peripheral surface of the synthetic resin rod with a rotating roller or the like, but the torque is indirectly applied through the fluid oil, the outer peripheral surface of the synthetic resin rod is not deformed. There is no fear that it will occur.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

1 to 5 show one embodiment of the present invention. FIG. 1 is a partial sectional perspective view of a roller having a two-layer structure manufactured by the manufacturing method of the present invention, and FIG. FIG. 3 is a process view showing a manufacturing process of a roller having a structure, FIG. 3 is a longitudinal sectional view showing the structure of a two-layer coextrusion molding machine, and FIG. 4 is a perspective view showing the shape of a nipple incorporated in the two-layer coextrusion molding machine. FIG. 4 is a cross-sectional view showing the structure of a rotation imparting machine. The constituent elements having the same functions as those of the conventional example shown in FIG. 6 are designated by the same reference numerals.

First, the structure of the roller 1 manufactured by the manufacturing method of this embodiment will be described with reference to FIG. The roller 1 has a two-layer structure in which the outer periphery of a hard synthetic resin inner layer portion 2 is covered with another synthetic resin outer layer portion 3. The inner layer portion 2 is a rod-shaped body in which a large number of spiral grooves 2a are formed on the cylindrical side surface. That is, each groove 2a is formed so as to extend generally along the axial direction of the inner layer portion 2, but as the groove 2a advances along the axis, the grooves 2a are sequentially twisted in the rotational direction of this axis. Further, in the present embodiment, each groove 2a of the inner layer portion 2 is a recess having a V-shaped cross section, and 12 grooves are formed at intervals of 30 ° over the entire circumference of the peripheral side surface. Therefore, the inner layer portion 2 has a star-shaped cross section, and the envelope surface of the twelve grooves 2a forms a cylindrical peripheral side surface. However, in the present invention, the shape of each groove 2a is arbitrary, and the number of threads and the formation interval are not limited to this.

The hard synthetic resin used for the inner layer 2 is
In order to maintain the straightness of the roller 1 instead of the metal rod, it is required to have excellent mechanical properties and good dimensional stability. Further, in applications such as an automatic developing machine for photographs, high chemical resistance to a developing solution and the like is also required. Moreover, as will be described later, when the inner layer portion 2 and the outer layer portion 3 are integrally molded by the two-layer coextrusion molding method, it is necessary to use a thermoplastic synthetic resin. Polyphenylene oxide (PPO) is an example of a synthetic resin that satisfies all of these conditions. The synthetic resin used for the inner layer portion 2 may be mixed with inorganic or organic fibers or any other filler in order to improve the strength.

The outer layer portion 3 is a cylindrical portion coated on the outer periphery of the peripheral side surface of the inner layer portion 2. Therefore, the cylindrical inner peripheral surface of the outer layer portion 3 enters into each groove 2 a of the inner layer portion 2. That is, a plurality of ridge lines protruding inward are formed in a spiral shape on the cylindrical inner peripheral surface of the outer layer portion 3, and each of these ridge lines is in close contact with and meshes with each groove 2a of the inner layer portion 2. become. The outer peripheral surface of the outer layer portion 3 is usually formed as a cylindrical surface coaxial with the inner layer portion 2, and has a highly smooth surface state when used in an automatic developing machine or the like. However, in the present invention, the shape and surface condition of the outer peripheral surface of the outer layer portion 3 are arbitrary and can be appropriately formed according to the application.

A soft synthetic resin is usually used for the outer layer portion 3. The soft synthetic resin referred to here includes synthetic rubber such as polyurethane rubber and silicone rubber. That is, the term “synthetic resin” may include a definition that does not include synthetic rubber, but the term “synthetic resin” other than hard used in the present specification includes this synthetic rubber. The outer layer portion 3 may be made of a hard synthetic resin having a composition different from that of the inner layer portion 2 depending on the use. The synthetic resin used for the outer layer portion 3 is also required to have high chemical resistance in applications such as automatic developing machines. Also, the inner layer portion 2
As in the case of (1), a thermoplastic synthetic resin is necessary for integrally molding by the two-layer coextrusion molding method. The thermoplastic elastomer is a general term for thermoplastic synthetic rubber and the like, and is a preferable material for the outer layer portion 3. However, when another manufacturing method is used, it does not necessarily have to be thermoplastic, and a thermosetting synthetic resin or synthetic rubber can also be used.

This double-layered roller 1 having the above structure
Even if peeling occurs at the interface between the inner layer portion 2 and the outer layer portion 3 due to a difference in heat shrinkage ratio between the inner layer portion 2 and the outer layer portion 3, for example, the groove 2a
Since the ridgeline of the inner peripheral surface of the outer layer portion 3 enters into and is meshed with the inner layer portion 3, the inner layer portion 2 and the outer layer portion 3 are prevented from idling. Moreover, since each groove 2a of the inner layer portion 2 is formed in a spiral shape, there is no possibility that the outer layer portion 3 shifts in the axial direction. In addition, when each groove 2a is accurately formed in a spiral shape with an equal pitch, there is an undeniable possibility that the outer layer portion 3 is axially displaced while rotating like a nut screwed with a bolt. However, also in this case, since the frictional resistance is much larger than that in the case where each groove 2a is linear, the outer layer portion 3 is hardly displaced actually.

Next, a method of manufacturing the roller 1 will be described. In this manufacturing method, since the two-layer simultaneous extrusion molding method is used, a thermoplastic synthetic resin is used for the inner layer portion 2 and the outer layer portion 3. As these synthetic resins, it is preferable to use polyphenylene oxide for the inner layer portion 2 and a thermoplastic elastomer for the outer layer portion 3.

These thermoplastic synthetic resin materials are shown in FIG.
As shown in (1), it is supplied to the two-layer simultaneous extrusion molding machine 10 in a state of being heated and melted, and extrusion-molded. As shown in FIG. 3, the two-layer co-extrusion molding machine 10 has a substantially funnel-shaped nipple 12 arranged in a mold 11, and pushes out the synthetic resin 4 of the inner layer portion 2 through the inner diameter of the nipple 12. By supplying the synthetic resin 5 of the outer layer portion 3 from the hopper 13 to the outer circumference of the nipple 12, two layers of these synthetic resins 4 and 5 are simultaneously extrusion-molded. The nipple 12 is shown in FIG.
As shown in FIG. 3, the substantially funnel-shaped tip portion 12a has a thin-walled cylindrical shape, and a linear recessed portion 12b along the axial direction in which the peripheral wall of the cylindrical shape is recessed toward the center is formed over the entire circumference. Twelve places are provided at intervals. Therefore, the synthetic resin 4 that has passed through the inner diameter of the nipple 12 is molded as a columnar inner layer portion 2 having twelve linear grooves 2a on the peripheral side surface. The synthetic resin 5 supplied from the outer peripheral side of the nipple 12 is coated on the outer periphery of the inner layer portion 2 to be molded as the outer layer portion 3. Further, the outer peripheral surface of the outer layer portion 3 is molded by the mold 11 into a cylindrical surface coaxial with the inner layer portion 2 and having high smoothness. The two-layer simultaneous extrusion molding machine 10
In the two-layer simultaneous extrusion molding process according to (1), the shape and the number of grooves 2a on the peripheral side surface of the inner layer portion 2 are arbitrary, and the shape and surface state of the outer peripheral surface of the outer layer portion 3 are also arbitrary.

As shown in FIG. 3, the two-layer structure synthetic resin rod 6 extruded by the two-layer simultaneous extrusion molding machine 10 is as shown in FIG.
It is inserted into the long ground die 20. As shown in FIG. 2, the long land die 20 is a long die having a predetermined inner diameter, and this inlet portion serves as a molding region to continue molding the outer diameter of the synthetic resin rod 6 and thereafter. The cooling is performed in the cooling area of the above to solidify the synthetic resins 4 and 5 of the synthetic resin rod 6. When the synthetic resin rod 6 is solidified in such a long long ground die 20 having a predetermined inner diameter,
It is possible to obtain an outer peripheral surface having high smoothness with almost no change in outer diameter. In addition, as a cooling method of the cooling area, FIG.
It is possible to use any method such as taking a cold water shower from above the long land die 20 as shown in FIG. 2 or providing a running water jacket on this long land die 20 to circulate cooling water there.

A synthetic resin rod 6 having a two-layer structure solidified in the long-land die process by the long-land die 20.
Is applied with a torque about the axis of rotation by the rotation imparting machine 30. As shown in FIG. 5, the rotation imparting machine 30 includes a rotary die 32 that is rotationally driven by a motor 31.
Is equipped with. Then, the synthetic resin rod 6 is inserted into the inner diameter of the rotary die 32 with a gap. Oil 33 is filled in the gap between the inner peripheral surface of the rotary die 32 and the outer peripheral surface of the synthetic resin rod 6. This oil 33
For example, it can be held by a packing that rotatably seals between the inlet and outlet of the inner diameter of the rotary die 32 and the outer peripheral surface of the synthetic resin rod 6. Further, the clearance between the inner surface of the rotary die 32 and the inner peripheral surface may be sufficiently narrowed, and lubricating oil may be sequentially supplied to the clearance. When the rotary die 32 of the rotation imparting machine 30 is rotated by the motor 31, the oil 33 also rotates around the synthetic resin rod 6 accordingly.
Then, when the oil 33 rotates, torque is applied to the entire outer peripheral surface of the synthetic resin rod 6 accordingly, and the solidified synthetic resin rod 6 rotates entirely. That is, rotary die 3
The rotation of 2 is transmitted to the synthetic resin rod 6 by hydrocoupling due to the viscosity of the oil 33. At this time, the synthetic resin rod 6 is rotated at a slower speed than the rotary die 32, so that an appropriate torque is applied.

This rotation imparting machine 30 is used for the synthetic resin rod 6
When a torque is applied to the synthetic resin rod 6 which is cooled and solidified in the longland die 20, the synthetic resin rod 6 also rotates.
Therefore, in the long land die 20, the solidified synthetic resin rods 6 sequentially rotate, so that the unsolidified synthetic resin rods 6 are twisted, and the grooves 2a of the inner layer portion 2 are linearly shown in FIG. It changes like a spiral. Further, since the outer diameter of the synthetic resin rod 6 is regulated in the long land die 20, even if such a twist is applied to the unsolidified portion,
The synthetic resin rod 6 will not be twisted and bent, or solidified in a state where the outer diameter is not uniform. Moreover, since the synthetic resin rods 6 which have begun to solidify in the cooling region are sequentially rotated in the longland die 20, the circumferential cooling of the synthetic resins 4 and 5 is made uniform, so that the cooling is non-uniform. It is possible to prevent the occurrence of bending due to, and the straightness is improved.

The rotation imparting machine 30 is not limited to the one which imparts the torque by the above-described method, but the torque is imparted by sliding a plurality of rotating rollers around the synthetic resin rod 6, for example. It may be one. However, as shown in the present embodiment, if a torque is applied through the oil 33 by hydrocoupling, a force is uniformly applied to the entire outer peripheral surface of the synthetic resin rod 6, so that the rotating roller, etc. There is no possibility of deformation due to contact between the and the smoothness being impaired.

The synthetic resin rod 6 which has been subjected to the rotation imparting process by the rotation imparting machine 30 is sent to the washing machine 40 and the oil 3 is supplied.
3 is washed off and then cut by a roller cutting machine 50 into a proper length (for example, 20 to 30 cm), as shown in FIG.
The roller 1 shown in FIG. The step of washing the synthetic resin rod 6 by the washing machine 40 can be omitted. Further, in addition to this cleaning step or instead of this cleaning step, other steps such as surface treatment of the outer peripheral surface of the synthetic resin rod 6 can be inserted.

According to the above-mentioned manufacturing method, the two-layer simultaneous extrusion molding machine 10 extrudes the two-layer structure synthetic resin rod 6 having the groove 2a formed in the inner layer portion 2, and the rotation imparting machine 30 uses this synthetic resin rod. Since torque is applied to the groove 6, the groove 2a of the inner layer portion 2
It is possible to obtain the roller 1 having a spiral twist. Also,
Since the synthetic resin rod 6 is twisted during solidification in the long land die 20, the outer diameter of the roller 1 does not become nonuniform, and the straightness is improved. Moreover, since the rotation imparting machine 30 imparts a torque to the synthetic resin rod 6 via the oil 33, there is no possibility that the outer peripheral surface of the roller 1 is deformed.

[0026]

As is apparent from the above description, according to the method of manufacturing a roller having a two-layer structure of claim 1, a two-layer structure synthetic resin rod having grooves formed in the inner layer portion by two-layer coextrusion molding is used. By molding and twisting this synthetic resin rod, the groove of this inner layer part can be made almost spiral, so that the outer layer part does not slip and the outer layer part does not shift in the axial direction. A roller can be obtained. Further, the straightness of the roller having the two-layer structure can be improved by using the long-land die.

Further, according to the method for manufacturing a roller having a two-layer structure according to claim 2, since torque is applied to the synthetic resin rod by hydrocoupling via oil, deformation of the outer peripheral surface of the roller may occur. Also disappears.

Further, according to the two-layer structure roller manufactured by the manufacturing method of the present invention, even if the interface between the inner layer portion and the outer layer portion is separated, the inner peripheral surface of the outer layer portion is formed in the groove of the inner layer portion. Since it has entered, the inner layer portion and the outer layer portion do not spin idle. Moreover, since the groove of the inner layer portion is twisted in a substantially spiral shape, there is no possibility that the outer layer portion is displaced in the axial direction.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional perspective view of a roller having a two-layer structure manufactured by a manufacturing method of the present invention.

FIG. 2 shows an embodiment of the present invention and is a front view showing a manufacturing process of a roller having a two-layer structure.

FIG. 3 shows an embodiment of the present invention and is a vertical cross-sectional front view showing the structure of a two-layer coextrusion molding machine.

FIG. 4 shows an embodiment of the present invention and is a perspective view showing a shape of a nipple incorporated in a two-layer coextrusion molding machine.

FIG. 5 is a cross-sectional side view showing the structure of the rotation imparting machine, showing the embodiment of the present invention.

FIG. 6 shows a conventional example and is a partial cross-sectional perspective view of a roller having a two-layer structure.

[Explanation of symbols]

1 roller 2 Inner layer 2a groove 3 outer layer 4 synthetic resin 5 synthetic resin 6 synthetic resin rod 10 Two layer coextrusion machine 20 Ron Grand Dice 30 rotation imparting machine 33 oil 50 roller cutting machine

─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Seiichi Hiraoka 663 Minoshima, Arita-shi, Wakayama Mitsubishi Cable Industries, Ltd.Minoshima Works (72) Inventor Hiroyuki Sato 798, Miyadai, Kaisei-cho, Ashigara-gun, Kanagawa Fuji Photo Film Co., Ltd. (56) References Actual Open Sho 63-21040 (JP, U) Actual Open Flat 5-92533 (JP, U) Actual Open Sho 64-14921 (JP, U) Actual Open Sho 63-21040 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) B29C 47/00-47/96 B29D 31/00-31/02 F16C 13/00-15/00

Claims (2)

(57) [Claims] 1. A hard thermoplastic thermoplastic resin is extruded to form a cylindrical inner layer portion having a plurality of grooves on the peripheral side surface, and the outer periphery of this inner layer portion is coated with another thermoplastic synthetic resin. The two-layer coextrusion molding step of extruding a two-layer structure synthetic resin rod by molding the outer layer part with the outer layer part, and the two-layer structure synthetic resin rod extruded by this two-layer coextrusion molding step with a predetermined inner diameter A long-land die process in which it is inserted into a long long-land die for cooling, and a rotation that applies torque about the axis to a synthetic resin rod with a two-layer structure solidified by cooling in this long-land die process to apply twist A roller having a two-layer structure characterized by including a applying step and a roller cutting step of cutting a synthetic resin rod having a two-layer structure, which has been twisted in the rotation applying step, into a roller by cutting it into an appropriate length. Production method. 2. The rotation applying step fills the periphery of a synthetic resin rod having a two-layer structure solidified in the long ground die step with oil, and applies torque by rotating the oil around the synthetic resin. The method for manufacturing a roller having a two-layer structure according to claim 1, wherein